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Rumors => Lenses => Topic started by: IsaacImage on May 22, 2014, 10:57:38 PM

Title: Sigma 50mm Art 1.4 Focusing problems
Post by: IsaacImage on May 22, 2014, 10:57:38 PM
Hello dear friends

After 4 copies of Sigma I'm a bit disappointed.
It's a gorgeous piece of glass but needs adjustments.
All copies are front focusing from the beginning and needs +13 or +17 depends on bodies.
So I decided to return and wait a bit longer.
Really don't think new lens should be adjusted at all !!!
Especially when Canon's 50L hit every single time…. but it's much softer 

Please share your experience with this lens.

(http://i.imgur.com/IAr4ZzJ.jpg)
(http://i.imgur.com/VmXGISU.jpg)

Title: Re: Sigma 50mm Art 1.4 Focusing problems
Post by: kaihp on May 23, 2014, 01:58:22 AM
After 4 copies of Sigma I'm a bit disappointed.
It's a gorgeous piece of glass but needs adjustments.
All copies are front focusing from the beginning and needs +13 or +17 depends on bodies.
So I decided to return and wait a bit longer.
Really don't think new lens should be adjusted at all !!!

Please share your experience with this lens.

Are those adjustments consistent, or do you need to change the AFMA from time to time, that's the real question to ask yourself. We have two forum members who have had to return their 50A lenses to Sigma because they couldn't focus reliably. Sure, 13-17 is a lot, but consistent (correct) focus beats inconsistent focus every time.

Please have a look at the http://www.canonrumors.com/forum/index.php?topic=20723.0 (http://www.canonrumors.com/forum/index.php?topic=20723.0) thread.
Title: Re: Sigma 50mm Art 1.4 Focusing problems
Post by: IsaacImage on May 23, 2014, 02:32:31 AM
After 4 copies of Sigma I'm a bit disappointed.
It's a gorgeous piece of glass but needs adjustments.
All copies are front focusing from the beginning and needs +13 or +17 depends on bodies.
So I decided to return and wait a bit longer.
Really don't think new lens should be adjusted at all !!!

Please share your experience with this lens.

Are those adjustments consistent, or do you need to change the AFMA from time to time, that's the real question to ask yourself. We have two forum members who have had to return their 50A lenses to Sigma because they couldn't focus reliably. Sure, 13-17 is a lot, but consistent (correct) focus beats inconsistent focus every time.

Please have a look at the http://www.canonrumors.com/forum/index.php?topic=20723.0 (http://www.canonrumors.com/forum/index.php?topic=20723.0) thread.

Unfortunately it's a very inconsistent results, more like hit and miss, at least on two of the lenses.
 
Title: Re: Sigma 50mm Art 1.4 Focusing problems
Post by: candyman on May 23, 2014, 02:38:04 AM
After 4 copies of Sigma I'm a bit disappointed.
It's a gorgeous piece of glass but needs adjustments.
All copies are front focusing from the beginning and needs +13 or +17 depends on bodies.
So I decided to return and wait a bit longer.
Really don't think new lens should be adjusted at all !!!

Please share your experience with this lens.

Are those adjustments consistent, or do you need to change the AFMA from time to time, that's the real question to ask yourself. We have two forum members who have had to return their 50A lenses to Sigma because they couldn't focus reliably. Sure, 13-17 is a lot, but consistent (correct) focus beats inconsistent focus every time.

Please have a look at the http://www.canonrumors.com/forum/index.php?topic=20723.0 (http://www.canonrumors.com/forum/index.php?topic=20723.0) thread.

Unfortunately it's a very inconsistent results, more like hit and miss, at least on two of the lenses.

Did you use Focal software for AFMA or manually with a product like Spyder LensCal?
Title: Re: Sigma 50mm Art 1.4 Focusing problems
Post by: IsaacImage on May 23, 2014, 02:54:16 AM
After 4 copies of Sigma I'm a bit disappointed.
It's a gorgeous piece of glass but needs adjustments.
All copies are front focusing from the beginning and needs +13 or +17 depends on bodies.
So I decided to return and wait a bit longer.
Really don't think new lens should be adjusted at all !!!

Please share your experience with this lens.

Are those adjustments consistent, or do you need to change the AFMA from time to time, that's the real question to ask yourself. We have two forum members who have had to return their 50A lenses to Sigma because they couldn't focus reliably. Sure, 13-17 is a lot, but consistent (correct) focus beats inconsistent focus every time.

Please have a look at the http://www.canonrumors.com/forum/index.php?topic=20723.0 (http://www.canonrumors.com/forum/index.php?topic=20723.0) thread.

Unfortunately it's a very inconsistent results, more like hit and miss, at least on two of the lenses.

Did you use Focal software for AFMA or manually with a product like Spyder LensCal?

With Spyder Lenscal only…. didn't have much time for the Focal
Title: Re: Sigma 50mm Art 1.4 Focusing problems
Post by: candyman on May 23, 2014, 03:03:41 AM
After 4 copies of Sigma I'm a bit disappointed.
It's a gorgeous piece of glass but needs adjustments.
All copies are front focusing from the beginning and needs +13 or +17 depends on bodies.
So I decided to return and wait a bit longer.
Really don't think new lens should be adjusted at all !!!

Please share your experience with this lens.

Are those adjustments consistent, or do you need to change the AFMA from time to time, that's the real question to ask yourself. We have two forum members who have had to return their 50A lenses to Sigma because they couldn't focus reliably. Sure, 13-17 is a lot, but consistent (correct) focus beats inconsistent focus every time.

Please have a look at the http://www.canonrumors.com/forum/index.php?topic=20723.0 (http://www.canonrumors.com/forum/index.php?topic=20723.0) thread.

Unfortunately it's a very inconsistent results, more like hit and miss, at least on two of the lenses.

Did you use Focal software for AFMA or manually with a product like Spyder LensCal?

With Spyder Lenscal only…. didn't have much time for the Focal

Seems to exclude a theory but I am no techie. I thought that maybe the Sigma circuitboard can not handle the Focal AFMA software adjustments and could be a reason that after the AFMA with Focal the Lens is totally screwed.
Oh well, it is really a pitty for Sigma and this lens that the saga with AF seems to continue. For now, I don't have problems with the 50A on my 6D. I need to do some checking on the 5D MKIII. I can't believe the Sigma has problems with specific the 61-points AF of the 1DX and 5D MKIII. I am sure that Sigma did a good checking on that since they this is an very desirable target group for their 50A.
Title: Re: Sigma 50mm Art 1.4 Focusing problems
Post by: IsaacImage on May 23, 2014, 03:20:24 AM
let's wait and see how Sigma going to handle it.
As for me I'm in love with this lens and want this lens so bad…… but those "Hit and miss" games remind me d800 days and I don't want to play this shitty game again
Title: Re: Sigma 50mm Art 1.4 Focusing problems
Post by: Eldar on May 23, 2014, 04:23:45 AM
I just got my replacement lens. I have not had time to run it through FoCal yet, but did a quick test on LensAlign. To begin with, there is no need for adjustment on this one, but I need more time to see if the inconsistencies appear on this one also.

Regarding Sigma and FoCal; FoCal gives information to use with the camera, not the lens. You adjust the AFMA on the body. On a 1DX and 5DIII, as I have, you even have to do all the adjustments manually. The only adjustment that influences the lens is done through Sigma´s own USB dock.
Title: Re: Sigma 50mm Art 1.4 Focusing problems
Post by: candyman on May 23, 2014, 04:56:52 AM
I just got my replacement lens. I have not had time to run it through FoCal yet, but did a quick test on LensAlign. To begin with, there is no need for adjustment on this one, but I need more time to see if the inconsistencies appear on this one also.

Regarding Sigma and FoCal; FoCal gives information to use with the camera, not the lens. You adjust the AFMA on the body. On a 1DX and 5DIII, as I have, you even have to do all the adjustments manually. The only adjustment that influences the lens is done through Sigma´s own USB dock.


Good to hear you got a replacement and good to hear the first sign is a good one.
Thanks for your explanation about focal / camera / lens.


I used the dock for firmware upgrade only
Title: Re: Sigma 50mm Art 1.4 Focusing problems
Post by: Viggo on May 23, 2014, 06:43:56 AM
4 copies? Ouch, more of the same experience I have, and mine is awaiting a new motherboard.

Mine was between +11 and +17 and the different distances , but then one day I also had to add +12 in camera to get anything focused right. So all I can say is +1 to your experience, mine was the exact same way.

I will update in the ongoing thread about the 50 Art when I get it back.
But this does not give me very high hopes...
Title: Re: Sigma 50mm Art 1.4 Focusing problems
Post by: IsaacImage on May 23, 2014, 07:37:19 AM
I just got my replacement lens. I have not had time to run it through FoCal yet, but did a quick test on LensAlign. To begin with, there is no need for adjustment on this one, but I need more time to see if the inconsistencies appear on this one also.

Regarding Sigma and FoCal; FoCal gives information to use with the camera, not the lens. You adjust the AFMA on the body. On a 1DX and 5DIII, as I have, you even have to do all the adjustments manually. The only adjustment that influences the lens is done through Sigma´s own USB dock.

Glad to  hear that Eldar !

So all the in camera adjustments are not effective ? and it's must to have USB dock to adjust the 50th ?
Title: Re: Sigma 50mm Art 1.4 Focusing problems
Post by: IsaacImage on May 23, 2014, 07:39:54 AM
4 copies? Ouch, more of the same experience I have, and mine is awaiting a new motherboard.

Mine was between +11 and +17 and the different distances , but then one day I also had to add +12 in camera to get anything focused right. So all I can say is +1 to your experience, mine was the exact same way.

I will update in the ongoing thread about the 50 Art when I get it back.
But this does not give me very high hopes...

Definitely something wrong with the first batch.
But after all those years I think Sigma should be very careful especially with the first shipments of their product, to keep the brand high !
As it's not easy to recover the brand.
Title: Re: Sigma 50mm Art 1.4 Focusing problems
Post by: Eldar on May 23, 2014, 09:03:25 AM
I just got my replacement lens. I have not had time to run it through FoCal yet, but did a quick test on LensAlign. To begin with, there is no need for adjustment on this one, but I need more time to see if the inconsistencies appear on this one also.

Regarding Sigma and FoCal; FoCal gives information to use with the camera, not the lens. You adjust the AFMA on the body. On a 1DX and 5DIII, as I have, you even have to do all the adjustments manually. The only adjustment that influences the lens is done through Sigma´s own USB dock.

Glad to  hear that Eldar !

So all the in camera adjustments are not effective ? and it's must to have USB dock to adjust the 50th ?
With the dock you can adjust the total focus from MFD to infinity in 4 sections. I have not figured out the scale yet, but you can do a +/-20 adjustment, just like in FoCal, so it might be that it is same same. For this lens (and the 35 Art) Sigma should have calibrated them prior to shipping though ...
Title: Re: Sigma 50mm Art 1.4 Focusing problems
Post by: Viggo on May 23, 2014, 09:08:21 AM
4 copies? Ouch, more of the same experience I have, and mine is awaiting a new motherboard.

Mine was between +11 and +17 and the different distances , but then one day I also had to add +12 in camera to get anything focused right. So all I can say is +1 to your experience, mine was the exact same way.

I will update in the ongoing thread about the 50 Art when I get it back.
But this does not give me very high hopes...

Definitely something wrong with the first batch.
But after all those years I think Sigma should be very careful especially with the first shipments of their product, to keep the brand high !
As it's not easy to recover the brand.

I think the issue is much more serious than a first batch problem, myself an others had the same issues with the 35 Art as well. All I can say is that if my 50 Art doesn't work after repair, I'm sooo done with Sigma ..
Title: Re: Sigma 50mm Art 1.4 Focusing problems
Post by: IsaacImage on May 23, 2014, 09:14:22 AM
4 copies? Ouch, more of the same experience I have, and mine is awaiting a new motherboard.

Mine was between +11 and +17 and the different distances , but then one day I also had to add +12 in camera to get anything focused right. So all I can say is +1 to your experience, mine was the exact same way.

I will update in the ongoing thread about the 50 Art when I get it back.
But this does not give me very high hopes...



Definitely something wrong with the first batch.
But after all those years I think Sigma should be very careful especially with the first shipments of their product, to keep the brand high !
As it's not easy to recover the brand.

I think the issue is much more serious than a first batch problem, myself an others had the same issues with the 35 Art as well. All I can say is that if my 50 Art doesn't work after repair, I'm sooo done with Sigma ..

In my case I got 35 Art from the first batch.
And zero … yes ZERO problems !!!

Title: Re: Sigma 50mm Art 1.4 Focusing problems
Post by: Viggo on May 23, 2014, 09:19:29 AM
4 copies? Ouch, more of the same experience I have, and mine is awaiting a new motherboard.

Mine was between +11 and +17 and the different distances , but then one day I also had to add +12 in camera to get anything focused right. So all I can say is +1 to your experience, mine was the exact same way.

I will update in the ongoing thread about the 50 Art when I get it back.
But this does not give me very high hopes...



Definitely something wrong with the first batch.
But after all those years I think Sigma should be very careful especially with the first shipments of their product, to keep the brand high !
As it's not easy to recover the brand.

I think the issue is much more serious than a first batch problem, myself an others had the same issues with the 35 Art as well. All I can say is that if my 50 Art doesn't work after repair, I'm sooo done with Sigma ..

In my case I got 35 Art from the first batch.
And zero … yes ZERO problems !!!

Exactly..
Title: Re: Sigma 50mm Art 1.4 Focusing problems
Post by: aznable on May 24, 2014, 03:34:54 PM
got my 50 Art two days ago...perfect with 50D a a pronunced FF with 1dmk3....solution....fine tune with the dock, now the focus is good with 1dmk3 and with in body regulation with 50D, now i get good results with both bodies
Title: Re: Sigma 50mm Art 1.4 Focusing problems
Post by: Viggo on May 24, 2014, 03:47:16 PM
got my 50 Art two days ago...perfect with 50D a a pronunced FF with 1dmk3....solution....fine tune with the dock, now the focus is good with 1dmk3 and with in body regulation with 50D, now i get good results with both bodies

Yes, so was Eldar's and mine also, shoot another 4000 images in and out and see if it changes .
Title: Re: Sigma 50mm Art 1.4 Focusing problems
Post by: aznable on May 24, 2014, 03:56:28 PM
got my 50 Art two days ago...perfect with 50D a a pronunced FF with 1dmk3....solution....fine tune with the dock, now the focus is good with 1dmk3 and with in body regulation with 50D, now i get good results with both bodies

Yes, so was Eldar's and mine also, shoot another 4000 images in and out and see if it changes .

4k? too much  ;)

the focus is consistent tough
Title: Re: Sigma 50mm Art 1.4 Focusing problems
Post by: Viggo on May 24, 2014, 04:07:11 PM
got my 50 Art two days ago...perfect with 50D a a pronunced FF with 1dmk3....solution....fine tune with the dock, now the focus is good with 1dmk3 and with in body regulation with 50D, now i get good results with both bodies

Yes, so was Eldar's and mine also, shoot another 4000 images in and out and see if it changes .

4k? too much  ;)

the focus is consistent tough

I have three batteries, just run through three batteries and you have shot 4000 images. Do half and you still be able to see the drift is there..
Title: Re: Sigma 50mm Art 1.4 Focusing problems
Post by: aznable on May 24, 2014, 04:49:58 PM
got my 50 Art two days ago...perfect with 50D a a pronunced FF with 1dmk3....solution....fine tune with the dock, now the focus is good with 1dmk3 and with in body regulation with 50D, now i get good results with both bodies

Yes, so was Eldar's and mine also, shoot another 4000 images in and out and see if it changes .

4k? too much  ;)

the focus is consistent tough

I have three batteries, just run through three batteries and you have shot 4000 images. Do half and you still be able to see the drift is there..

i will try with focal, but the beaviour of the lens seems normal with autofocus system of 1D series....also in lenstip.com review the lens was has pronunced FF with 1d series + inconsistency

dwhich kind of problems had with your 50 Art?
Title: Re: Sigma 50mm Art 1.4 Focusing problems
Post by: Viggo on May 24, 2014, 05:15:40 PM
got my 50 Art two days ago...perfect with 50D a a pronunced FF with 1dmk3....solution....fine tune with the dock, now the focus is good with 1dmk3 and with in body regulation with 50D, now i get good results with both bodies

Yes, so was Eldar's and mine also, shoot another 4000 images in and out and see if it changes .

4k? too much  ;)

the focus is consistent tough

I have three batteries, just run through three batteries and you have shot 4000 images. Do half and you still be able to see the drift is there..

i will try with focal, but the beaviour of the lens seems normal with autofocus system of 1D series....also in lenstip.com review the lens was has pronunced FF with 1d series + inconsistency

dwhich kind of problems had with your 50 Art?

Adjusted with FoCal and plotted the numbers into the lens via the docking. It was flawless, absolutely spot on, FoCal showed 99,4% consistency with 30 shots, or better/same as the 24-70 and 200 f2. I loved it. But after a week it started to miss, a little or very badly, like 10 meters from subject. And it could be 5 metes behind, spot on and ten meters in front within three consecutive shots. Calibrated and adjusted new values, worked perfect again, for a while. And eventually I did t have more afma range to go to and it was all over, completely unstable and random.
Title: Re: Sigma 50mm Art 1.4 Focusing problems
Post by: aznable on May 24, 2014, 06:16:12 PM
got my 50 Art two days ago...perfect with 50D a a pronunced FF with 1dmk3....solution....fine tune with the dock, now the focus is good with 1dmk3 and with in body regulation with 50D, now i get good results with both bodies

Yes, so was Eldar's and mine also, shoot another 4000 images in and out and see if it changes .

4k? too much  ;)

the focus is consistent tough

I have three batteries, just run through three batteries and you have shot 4000 images. Do half and you still be able to see the drift is there..

i will try with focal, but the beaviour of the lens seems normal with autofocus system of 1D series....also in lenstip.com review the lens was has pronunced FF with 1d series + inconsistency

dwhich kind of problems had with your 50 Art?

Adjusted with FoCal and plotted the numbers into the lens via the docking. It was flawless, absolutely spot on, FoCal showed 99,4% consistency with 30 shots, or better/same as the 24-70 and 200 f2. I loved it. But after a week it started to miss, a little or very badly, like 10 meters from subject. And it could be 5 metes behind, spot on and ten meters in front within three consecutive shots. Calibrated and adjusted new values, worked perfect again, for a while. And eventually I did t have more afma range to go to and it was all over, completely unstable and random.

seems a very bad problem...i will take more shots, for now i taken just 2 hundreds
Title: Re: Sigma 50mm Art 1.4 Focusing problems
Post by: wickidwombat on May 24, 2014, 07:51:37 PM
4 copies? Ouch, more of the same experience I have, and mine is awaiting a new motherboard.

Mine was between +11 and +17 and the different distances , but then one day I also had to add +12 in camera to get anything focused right. So all I can say is +1 to your experience, mine was the exact same way.

I will update in the ongoing thread about the 50 Art when I get it back.
But this does not give me very high hopes...



Definitely something wrong with the first batch.
But after all those years I think Sigma should be very careful especially with the first shipments of their product, to keep the brand high !
As it's not easy to recover the brand.

I think the issue is much more serious than a first batch problem, myself an others had the same issues with the 35 Art as well. All I can say is that if my 50 Art doesn't work after repair, I'm sooo done with Sigma ..

In my case I got 35 Art from the first batch.
And zero … yes ZERO problems !!!
Ditto mine is amazing and probably the fastest most accurately focusing lens in low light that I own and have ever used
Title: Re: Sigma 50mm Art 1.4 Focusing problems
Post by: IsaacImage on May 24, 2014, 08:44:28 PM
te]
Ditto mine is amazing and probably the fastest most accurately focusing lens in low light that I own and have ever used
[/quote]

What body you are using it with ?
Most of the troubles with the newest 1dx or 5d mkiii's AF system
Title: Re: Sigma 50mm Art 1.4 Focusing problems
Post by: wickidwombat on May 24, 2014, 08:46:56 PM
te]
Ditto mine is amazing and probably the fastest most accurately focusing lens in low light that I own and have ever used

What body you are using it with ?
Most of the troubles with the newest 1dx or 5d mkiii's AF system
[/quote]
5d3 and eos m
Title: Re: Sigma 50mm Art 1.4 Focusing problems
Post by: IsaacImage on May 24, 2014, 08:52:02 PM
Small update from my side.
I'm on fifth copy.
+13 AF adjustments needed and far left and far right AF points are missing on 1dx.
Sounds like normal d800 problem ;) spoke to a Sigma rep. During the photo video expo today he told me to bring it to a service they definitely can adjust it..... Let's see how it goes.
Title: Re: Sigma 50mm Art 1.4 Focusing problems
Post by: wickidwombat on May 24, 2014, 09:01:48 PM
Small update from my side.
I'm on fifth copy.
+13 AF adjustments needed and far left and far right AF points are missing on 1dx.
Sounds like normal d800 problem ;) spoke to a Sigma rep. During the photo video expo today he told me to bring it to a service they definitely can adjust it..... Let's see how it goes.

Have you got the sigma dock? I just adjusted my 50 using the dock
Title: Re: Sigma 50mm Art 1.4 Focusing problems
Post by: IsaacImage on May 24, 2014, 09:19:17 PM
The USB Dock are not going to help as there is no any new firmware available yet.
The regular adjustments you can do in camera body.
And more complicated staff like adjustments per AF points you can not do with the dock anyway.
And I still believe that new lens should be adjusted and calibrated at the factory. ;)
Maybe I'm an old school guy ;)
Title: Re: Sigma 50mm Art 1.4 Focusing problems
Post by: kaihp on May 24, 2014, 09:34:46 PM
The USB Dock are not going to help as there is no any new firmware available yet.
The regular adjustments you can do in camera body.
And more complicated staff like adjustments per AF points you can not do with the dock anyway.
And I still believe that new lens should be adjusted and calibrated at the factory. ;)
Maybe I'm an old school guy ;)

The dock can do adjustments at four different subject distances. You cannot do that with the in-body AFMA.

So in this case, yes, you are a bit old-school. Nothing wrong with that, though - I like to shoot in M over Tv and Av modes, for example  ;D
Title: Re: Sigma 50mm Art 1.4 Focusing problems
Post by: wickidwombat on May 24, 2014, 09:49:17 PM
Yeah the do k allows you to adjust the lens properly to a degree that Afma in body simple cannot achieve
Title: Re: Sigma 50mm Art 1.4 Focusing problems
Post by: NancyP on May 24, 2014, 10:10:02 PM
50 Art users with focus problems - have you contacted Sigma? Has anyone thought to mention the issue to Roger Cicala, owner and geek extraordinaire of Lens Rental? He gets large numbers of lenses and is one of the few in the position to evaluate copy variation, durability, mechanical quirks. His review of the Sigma 50 Art was based on just a couple of lenses, but if enough people are interested, he might stock and test a bunch of the 50 Arts.
Title: Re: Sigma 50mm Art 1.4 Focusing problems
Post by: IsaacImage on May 25, 2014, 01:02:54 AM
50 Art users with focus problems - have you contacted Sigma? Has anyone thought to mention the issue to Roger Cicala, owner and geek extraordinaire of Lens Rental? He gets large numbers of lenses and is one of the few in the position to evaluate copy variation, durability, mechanical quirks. His review of the Sigma 50 Art was based on just a couple of lenses, but if enough people are interested, he might stock and test a bunch of the 50 Arts.

Absolutely agree Nancy
Lots of respect to Roger.
We need to drop him a line
Title: Re: Sigma 50mm Art 1.4 Focusing problems
Post by: Viggo on May 25, 2014, 02:53:04 AM
Small update from my side.
I'm on fifth copy.
+13 AF adjustments needed and far left and far right AF points are missing on 1dx.
Sounds like normal d800 problem ;) spoke to a Sigma rep. During the photo video expo today he told me to bring it to a service they definitely can adjust it..... Let's see how it goes.

Exactly the same with mine, +11-17 and far points absolutely doesn't work. Anyone know if the 50 Art can't utilize the cross type far right and left and simply uses cross type in the center instead of double cross type?
Title: Re: Sigma 50mm Art 1.4 Focusing problems
Post by: candyman on May 25, 2014, 04:21:02 AM
Small update from my side.
I'm on fifth copy.
+13 AF adjustments needed and far left and far right AF points are missing on 1dx.
Sounds like normal d800 problem ;) spoke to a Sigma rep. During the photo video expo today he told me to bring it to a service they definitely can adjust it..... Let's see how it goes.

Exactly the same with mine, +11-17 and far points absolutely doesn't work. Anyone know if the 50 Art can't utilize the cross type far right and left and simply uses cross type in the center instead of double cross type?

Viggo, I will do some checking with my 5D MKIII. You know, I am just an amateur and not having to much time working a lot and dealing with 2 young kids. Today is some nice weather so I will see what I can do.
Title: Re: Sigma 50mm Art 1.4 Focusing problems
Post by: YuengLinger on May 25, 2014, 06:07:43 AM
Viggo wrote:

"Exactly the same with mine, +11-17 and far points absolutely doesn't work. Anyone know if the 50 Art can't utilize the cross type far right and left and simply uses cross type in the center instead of double cross type?"

This might be the best question in this thread!
Title: Re: Sigma 50mm Art 1.4 Focusing problems
Post by: IsaacImage on May 25, 2014, 08:43:03 AM
Viggo wrote:

"Exactly the same with mine, +11-17 and far points absolutely doesn't work. Anyone know if the 50 Art can't utilize the cross type far right and left and simply uses cross type in the center instead of double cross type?"

This might be the best question in this thread!

100%
Title: Re: Sigma 50mm Art 1.4 Focusing problems
Post by: candyman on May 25, 2014, 10:05:16 AM
Ok, it turns out I did not have so much time today but here is an example. Please, help me to better understand your quest so I can share with you the results of my copy of lens



Title: Re: Sigma 50mm Art 1.4 Focusing problems
Post by: IsaacImage on May 26, 2014, 01:12:14 PM
Ok, it turns out I did not have so much time today but here is an example. Please, help me to better understand your quest so I can share with you the results of my copy of lens

It's a bit hard to judge by such a small files but looks sharp to me.
Title: Re: Sigma 50mm Art 1.4 Focusing problems
Post by: cid on May 26, 2014, 01:37:46 PM
And I thought it will be my fast prime in my set  :o  >:(

sadly there is no way I'm buying lens which has AF focus inconsistency, i they don't solve it, I'll rather give 35A a shot, or wait for 50L II
Title: Re: Sigma 50mm Art 1.4 Focusing problems
Post by: Viggo on May 26, 2014, 02:06:03 PM
And I thought it will be my fast prime in my set  :o  >:(

sadly there is no way I'm buying lens which has AF focus inconsistency, i they don't solve it, I'll rather give 35A a shot, or wait for 50L II

I had the same issue with the 35A, and I'm not alone in that.

If my new 50A doesn't work, I'll get my money back, and start saving for the lens I really had been waiting for, the 35 L II.
Title: Re: Sigma 50mm Art 1.4 Focusing problems
Post by: cid on May 26, 2014, 02:53:15 PM
And I thought it will be my fast prime in my set  :o  >:(

sadly there is no way I'm buying lens which has AF focus inconsistency, i they don't solve it, I'll rather give 35A a shot, or wait for 50L II

I had the same issue with the 35A, and I'm not alone in that.

If my new 50A doesn't work, I'll get my money back, and start saving for the lens I really had been waiting for, the 35 L II.

sad to hear that, except for these AF issue both these lenses look awesome ... well probably got to save for some canon (or maybe zeiss) glass
Title: Re: Sigma 50mm Art 1.4 Focusing problems
Post by: Viggo on May 26, 2014, 03:18:13 PM
And I thought it will be my fast prime in my set  :o  >:(

sadly there is no way I'm buying lens which has AF focus inconsistency, i they don't solve it, I'll rather give 35A a shot, or wait for 50L II

I had the same issue with the 35A, and I'm not alone in that.

If my new 50A doesn't work, I'll get my money back, and start saving for the lens I really had been waiting for, the 35 L II.

sad to hear that, except for these AF issue both these lenses look awesome ... well probably got to save for some canon (or maybe zeiss) glass

If you want some Zeiss, look into the 50mm f2 mp, it's fantastic and doubles as a macro. Only reason I sold it is because I simply can't get enough sharp shots with MF ..
Title: Re: Sigma 50mm Art 1.4 Focusing problems
Post by: cid on May 26, 2014, 03:21:23 PM
And I thought it will be my fast prime in my set  :o  >:(

sadly there is no way I'm buying lens which has AF focus inconsistency, i they don't solve it, I'll rather give 35A a shot, or wait for 50L II

I had the same issue with the 35A, and I'm not alone in that.

If my new 50A doesn't work, I'll get my money back, and start saving for the lens I really had been waiting for, the 35 L II.

sad to hear that, except for these AF issue both these lenses look awesome ... well probably got to save for some canon (or maybe zeiss) glass

If you want some Zeiss, look into the 50mm f2 mp, it's fantastic and doubles as a macro. Only reason I sold it is because I simply can't get enough sharp shots with MF ..

I know, I already had the opportunity to try it  ;)
Title: Re: Sigma 50mm Art 1.4 Focusing problems
Post by: Viggo on May 26, 2014, 03:30:18 PM
And I thought it will be my fast prime in my set  :o  >:(

sadly there is no way I'm buying lens which has AF focus inconsistency, i they don't solve it, I'll rather give 35A a shot, or wait for 50L II

I had the same issue with the 35A, and I'm not alone in that.

If my new 50A doesn't work, I'll get my money back, and start saving for the lens I really had been waiting for, the 35 L II.

sad to hear that, except for these AF issue both these lenses look awesome ... well probably got to save for some canon (or maybe zeiss) glass

If you want some Zeiss, look into the 50mm f2 mp, it's fantastic and doubles as a macro. Only reason I sold it is because I simply can't get enough sharp shots with MF ..

I know, I already had the opportunity to try it  ;)

That is what I really liked about the 50A, it could to very close shots with the same IQ as further away, something I hated that the 50 L couldn't do. And the 50A is completely distortion free and it did 1.4, something I disliked about the Zeiss. So of aaaall the 50's I have tried and owned, the 50A is seriously that optimal 50, in every way epic, IF the AF will work...
Title: Re: Sigma 50mm Art 1.4 Focusing problems
Post by: cid on May 26, 2014, 03:48:11 PM
That is what I really liked about the 50A, it could to very close shots with the same IQ as further away, something I hated that the 50 L couldn't do. And the 50A is completely distortion free and it did 1.4, something I disliked about the Zeiss. So of aaaall the 50's I have tried and owned, the 50A is seriously that optimal 50, in every way epic, IF the AF will work...

It's simply sad, it's like owning brand new bugatti veyron, but only with two wheels, so if you want to move it, you simply have to tow it ...
Title: Re: Sigma 50mm Art 1.4 Focusing problems
Post by: IsaacImage on May 30, 2014, 02:59:45 PM
Here is some update for the problem of this gorgeous lens.

After 5 days in service Sigma rep said "there is nothing to do with this right now and they waiting for firmware update for this lens."

Whole story on my blog with bunch of samples.

http://www.isaacimage.com/sigma-50mm-f1-4-dg-hsm-art/ (http://www.isaacimage.com/sigma-50mm-f1-4-dg-hsm-art/)
Title: Re: Sigma 50mm Art 1.4 Focusing problems
Post by: Viggo on May 30, 2014, 03:28:24 PM
Here is some update for the problem of this gorgeous lens.

After 5 days in service Sigma rep said "there is nothing to do with this right now and they waiting for firmware update for this lens."

Whole story on my blog with bunch of samples.

http://www.isaacimage.com/sigma-50mm-f1-4-dg-hsm-art/ (http://www.isaacimage.com/sigma-50mm-f1-4-dg-hsm-art/)

 Thanks for sharing. Interesting that they are working on a firmware update. And it's further supporting my thoughts about their utilizing, or rather not, of the cross type and double cross type AF points.

Interesting they say, "nothing to do right now" my new copy is 1800 pictures old and it's not hit and miss at. all.
Title: Re: Sigma 50mm Art 1.4 Focusing problems
Post by: YuengLinger on May 30, 2014, 04:47:36 PM
Here is some update for the problem of this gorgeous lens.

After 5 days in service Sigma rep said "there is nothing to do with this right now and they waiting for firmware update for this lens."

Whole story on my blog with bunch of samples.

http://www.isaacimage.com/sigma-50mm-f1-4-dg-hsm-art/ (http://www.isaacimage.com/sigma-50mm-f1-4-dg-hsm-art/)

In this thread, Viggo posted a hypothesis that, at least in some copies, the lens is not using the left and right AF points properly. He asked it very informally, sort of thinking out loud.

Yet you, Issac, state it almost factually in your blog:  "And it looks like Sigma can’t utilize the cross type of far right and far left and simply uses cross type in the center instead of double cross type sensors of 1dx and 5d mark 3 auto focus system."

C'mon.  This was one experienced photographer throwing out an idea.

And you seem to suggest that there is some kind of limitation to the lens when Sigma told you to use AFMA for the center point only.  Somebody correct me if I'm wrong, but don't we always use the center point for AFMA on all lenses? 

Furthermore, you go on to use at least one more quote from this thread, attributing it to "Somebody said," rather than properly citing your sources.  It's one thing to throw around rumors on a forum dedicated to RUMORS, but when you blog, you risk losing lots of credibility by not writing more...well, credibly.  Or professionally.

I can't help worrying about what my experience will be when I finally get mine, but I also can't help feeling that, with talk of going through five copies, "somebody" might just be a little over zealous in trying to find something wrong with the lens.  Something this new, makes sense to try one, try another, but I think you've lost some of the strength of whatever you were trying to accomplish in the first place.

Issac, I'm not trying to attack you or your integrity.  I'm merely pointing out, that in online battles for perception, companies often employ tactics of fear, uncertainty, and doubt--and quite effectively.  Corporations have been using "actors" for years to praise and criticize products.  And some brand loyalists are nutty enough to take it upon themselves.  It is only fair that claims good and bad be questioned, even met with skepticism.

Think about it.  This lens cannot be attacked because of image quality, an attribute way too easy to display by simply posting.  So the way to create doubt is to go after something less concrete, an ephemeral but potentially fatal AF problem. 

What's my stake in this?  I want a freakin' 50mm that works with great wide open performance.  I have several great L lenses, including the 85 and 135--and if a colleague and a legion of reviews hadn't put me off it, I'd have gone with the Canon 50mm 1.2 L.  I just know I wouldn't like the problems with close distance focusing, with CA, and with distortion, so I passed on it, using the 50mm 1.4 and other lenses instead.  That's it.  I want a lens that works, and I'm very happy Tamron and Sigma compete with Canon to put some price and quality pressure on.

You might very well feel the same way I do, yet on this site and others, I see crazy rants about how independent lens makers can never make decent lenses.  So I take EVERY post with a grain of salt until a critical mass of truthfulness and credibility is reached.
Title: Re: Sigma 50mm Art 1.4 Focusing problems
Post by: Viggo on May 30, 2014, 05:16:23 PM
Having had three sigma Art lenses and two of them useless with the same problem, I don't really doubt buying 5 from the first batch and they all show the same issue. Mine was also +17 and Eldar and others have had the same issue.

It's not a small single issue. It's a bunch of copies from the 35 and 50 Art. I didn't want them to be bad and all of us bought them to use them because the IQ is great.

It's almost offending to not believe our findings. And the thing about AF points is not a random statement, it's almost has to be that way when comparing to Canon lenses like the 85 L. Go from center towards the edges and it's clearly worse than the canon towards the edges. I know the 1dx AF system, and it's not fully functional with the 50 Art.
Title: Re: Sigma 50mm Art 1.4 Focusing problems
Post by: YuengLinger on May 30, 2014, 05:25:23 PM
Viggo, please don't take offense.  But please do understand how we all have to sort through a lot of misinformation on the web.  You've made quite clear with your long history of posts that you are sincere and knowledgeable.

Challenging findings and claims is the ONLY way to sort things out.
Title: Re: Sigma 50mm Art 1.4 Focusing problems
Post by: Rudeofus on May 30, 2014, 06:49:23 PM
I have read lots and lots of threads here with people having AF problems with the 50A, but so far all of them had these issues with their 1D series camera, most notably the 1Dx.

Can someone confirm that these issues also affect other cameras as well?
Title: Re: Sigma 50mm Art 1.4 Focusing problems
Post by: zlatko on May 30, 2014, 08:17:47 PM
Here is some update for the problem of this gorgeous lens.

After 5 days in service Sigma rep said "there is nothing to do with this right now and they waiting for firmware update for this lens."

Whole story on my blog with bunch of samples.

http://www.isaacimage.com/sigma-50mm-f1-4-dg-hsm-art/ (http://www.isaacimage.com/sigma-50mm-f1-4-dg-hsm-art/)

Sorry to hear such reports.  I'm going to stick with my now old 50/1.2L.  It's not a perfect 50, but it does its job and often makes a good photo.  It's actually one of my favorite lenses.
Title: Re: Sigma 50mm Art 1.4 Focusing problems
Post by: Random Orbits on May 30, 2014, 08:41:01 PM
I have read lots and lots of threads here with people having AF problems with the 50A, but so far all of them had these issues with their 1D series camera, most notably the 1Dx.

Can someone confirm that these issues also affect other cameras as well?

IsaacImage also mentioned having difficulties on the 5DIII, which has a similar AF system.  Being able to nail thin DOF shots with outer focus points is such a advantage that I don't think I'm willing to go back to using centerpoint only (i.e. 5DII) even if the lens is superior.
Title: Re: Sigma 50mm Art 1.4 Focusing problems
Post by: IsaacImage on May 30, 2014, 09:02:36 PM
I have read lots and lots of threads here with people having AF problems with the 50A, but so far all of them had these issues with their 1D series camera, most notably the 1Dx.

Can someone confirm that these issues also affect other cameras as well?

IsaacImage also mentioned having difficulties on the 5DIII, which has a similar AF system.  Being able to nail thin DOF shots with outer focus points is such a advantage that I don't think I'm willing to go back to using centerpoint only (i.e. 5DII) even if the lens is superior.

Yes it's exactly the same issues with 5d mk III
Title: Re: Sigma 50mm Art 1.4 Focusing problems
Post by: IsaacImage on May 30, 2014, 09:10:48 PM
Here is some update for the problem of this gorgeous lens.

After 5 days in service Sigma rep said "there is nothing to do with this right now and they waiting for firmware update for this lens."

Whole story on my blog with bunch of samples.

http://www.isaacimage.com/sigma-50mm-f1-4-dg-hsm-art/ (http://www.isaacimage.com/sigma-50mm-f1-4-dg-hsm-art/)

In this thread, Viggo posted a hypothesis that, at least in some copies, the lens is not using the left and right AF points properly. He asked it very informally, sort of thinking out loud.

Yet you, Issac, state it almost factually in your blog:  "And it looks like Sigma can’t utilize the cross type of far right and far left and simply uses cross type in the center instead of double cross type sensors of 1dx and 5d mark 3 auto focus system."

C'mon.  This was one experienced photographer throwing out an idea.

And you seem to suggest that there is some kind of limitation to the lens when Sigma told you to use AFMA for the center point only.  Somebody correct me if I'm wrong, but don't we always use the center point for AFMA on all lenses? 

Furthermore, you go on to use at least one more quote from this thread, attributing it to "Somebody said," rather than properly citing your sources.  It's one thing to throw around rumors on a forum dedicated to RUMORS, but when you blog, you risk losing lots of credibility by not writing more...well, credibly.  Or professionally.

I can't help worrying about what my experience will be when I finally get mine, but I also can't help feeling that, with talk of going through five copies, "somebody" might just be a little over zealous in trying to find something wrong with the lens.  Something this new, makes sense to try one, try another, but I think you've lost some of the strength of whatever you were trying to accomplish in the first place.

Issac, I'm not trying to attack you or your integrity.  I'm merely pointing out, that in online battles for perception, companies often employ tactics of fear, uncertainty, and doubt--and quite effectively.  Corporations have been using "actors" for years to praise and criticize products.  And some brand loyalists are nutty enough to take it upon themselves.  It is only fair that claims good and bad be questioned, even met with skepticism.

Think about it.  This lens cannot be attacked because of image quality, an attribute way too easy to display by simply posting.  So the way to create doubt is to go after something less concrete, an ephemeral but potentially fatal AF problem. 

What's my stake in this?  I want a freakin' 50mm that works with great wide open performance.  I have several great L lenses, including the 85 and 135--and if a colleague and a legion of reviews hadn't put me off it, I'd have gone with the Canon 50mm 1.2 L.  I just know I wouldn't like the problems with close distance focusing, with CA, and with distortion, so I passed on it, using the 50mm 1.4 and other lenses instead.  That's it.  I want a lens that works, and I'm very happy Tamron and Sigma compete with Canon to put some price and quality pressure on.

You might very well feel the same way I do, yet on this site and others, I see crazy rants about how independent lens makers can never make decent lenses.  So I take EVERY post with a grain of salt until a critical mass of truthfulness and credibility is reached.

Wow this post bigger than my blog post, are you boring or something ?
All written it's my personal thoughts and my personal experience and not scientific statement of official Canon rep.

I'm not telling you that I have enough experience even if I do have some ;), it's just make sense if you know when the cross type AF points and where double once and where Siggy is missing the target on 1dx body.

aLso had a bunch of troubles with 50L that's why I don't own one.
Cheers

George
Title: Re: Sigma 50mm Art 1.4 Focusing problems
Post by: Mt Spokane Photography on May 30, 2014, 09:52:28 PM
I long ago was bit by Sigma.  I had several EOS compatible lenses that would not work on DSLR's.  Sigma charged me $100 to fix one of them, the others were out of production, and paperweights.
 
Reverse engineering a lens Autofocus is extremely difficult.  The lens must give a camera a Canon lens code, and then the camera applies corrections and limitations based on a data table in the camera, so different camera generations might have some issues.  If the code given is for a lens that supports limited focus points, then you will only be able to use those points.
 
Assuming that you can use the Sigma Dock to get the lens perfect on a 5D MK III, it may still be horrible on a 7D or 1D MK IV.  That's the limitation of the dock, it adjusts for one camera only.
Title: Re: Sigma 50mm Art 1.4 Focusing problems
Post by: Viggo on May 30, 2014, 10:10:41 PM

 
Assuming that you can use the Sigma Dock to get the lens perfect on a 5D MK III, it may still be horrible on a 7D or 1D MK IV.  That's the limitation of the dock, it adjusts for one camera only.

Actually no, it adjusts the lens not the lens to a body. So the only thing you adjust is the normal afma. If my 1dx is at 0 and the lens adjusted at each distance to match that in camera adjustment, only thing I adjust on the 5d2 is the difference between those two bodies like I would any other lens. My gf's 5d2 is around -5 off the 1dx values. Dock adjusted lens and -5 in camera and it works.
Title: Re: Sigma 50mm Art 1.4 Focusing problems
Post by: Mt Spokane Photography on May 30, 2014, 10:31:09 PM

 
Assuming that you can use the Sigma Dock to get the lens perfect on a 5D MK III, it may still be horrible on a 7D or 1D MK IV.  That's the limitation of the dock, it adjusts for one camera only.

Actually no, it adjusts the lens not the lens to a body. So the only thing you adjust is the normal afma. If my 1dx is at 0 and the lens adjusted at each distance to match that in camera adjustment, only thing I adjust on the 5d2 is the difference between those two bodies like I would any other lens. My gf's 5d2 is around -5 off the 1dx values. Dock adjusted lens and -5 in camera and it works.

It adjusts the lens to match the camera its on.  That's what I was saying.  It then can be close, or way off on a different camera.  It depends on the actual adjustment accuracy of the camera you adjust it to.
 
I had a new 35mmL that was -2 on my 5D MK II but +17 on my 1D MK III.  Canon adjusted it for me, and it was right-on for both, and also at 0 AFMA when I upgraded to a 5D MK III.  I never could understand that. 
 
At plus five for the 5D MK III, that's fine.  But, if the lens changes over time, as some suggest, you have to recalibrate everything.
Title: Re: Sigma 50mm Art 1.4 Focusing problems
Post by: epsiloneri on May 31, 2014, 12:47:39 AM
Cameras are awesome devices, but they don't work by magic. Knowing a little bit about how the body and lens interact can be helpful in understanding and evaluating potential problems. The body detects how much out-of-focus an image is and sends a signal to the lens to adjust it, in one go in case of phase AF. The lens has to interpret this signal correctly and adjust properly; therein lies the software challenge for Sigma. The lens does not care how the body came to the conclusion that the particular adjustment was needed; ergo choosing focus point etc is entirely a body issue and has nothing to do with the lens (except in fringe cases such as the lens not illuminating the whole image plane - i.e. clearly a broken lens). As a corollary, the lenses' role for AF in low-light conditions is also questionable. Sure, faster lenses should give the body an easier time with more photons, but that's about it.

About AFMA, I would have expected the USB dock with AFMA to fix the relative AFMA of a lens, and the body to fix the absolute AFMA with respect to that particular body. You seem to say differently,Mt Spokane Photography. Why? Is this your expectation or actual experience? Once I get the dock and some time I could test multiple bodies with a single lens and FoCal to see how they correlate. Perhaps someone else has already tried that.
Title: Re: Sigma 50mm Art 1.4 Focusing problems
Post by: kaihp on May 31, 2014, 01:02:58 AM
Cameras are awesome devices, but they don't work by magic. Knowing a little bit about how the body and lens interact can be helpful in understanding and evaluating potential problems. The body detects how much out-of-focus an image is and sends a signal to the lens to adjust it, in one go in case of phase AF.

This (open loop focusing) was true previously, but Roger Cicala have found that newer Canon cameras do closed loop focusing (ie the PDAF system confirms the focus after the lens has moved).
Title: Re: Sigma 50mm Art 1.4 Focusing problems
Post by: epsiloneri on May 31, 2014, 02:03:18 AM
This (open loop focusing) was true previously, but Roger Cicala have found that newer Canon cameras do closed loop focusing (ie the PDAF system confirms the focus after the lens has moved).
Yes, that's right.
Title: Re: Sigma 50mm Art 1.4 Focusing problems
Post by: candyman on May 31, 2014, 02:32:11 AM
I have read lots and lots of threads here with people having AF problems with the 50A, but so far all of them had these issues with their 1D series camera, most notably the 1Dx.

Can someone confirm that these issues also affect other cameras as well?

IsaacImage also mentioned having difficulties on the 5DIII, which has a similar AF system.  Being able to nail thin DOF shots with outer focus points is such a advantage that I don't think I'm willing to go back to using centerpoint only (i.e. 5DII) even if the lens is superior.

Let's not forget that there are also people using a 5D MK III and do not have any problem with the 50Art. Mine works great. Couldn't be happier.
Just for the record, works great on my 6D too.
Title: Re: Sigma 50mm Art 1.4 Focusing problems
Post by: Viggo on May 31, 2014, 02:41:33 AM

 
Assuming that you can use the Sigma Dock to get the lens perfect on a 5D MK III, it may still be horrible on a 7D or 1D MK IV.  That's the limitation of the dock, it adjusts for one camera only.

Actually no, it adjusts the lens not the lens to a body. So the only thing you adjust is the normal afma. If my 1dx is at 0 and the lens adjusted at each distance to match that in camera adjustment, only thing I adjust on the 5d2 is the difference between those two bodies like I would any other lens. My gf's 5d2 is around -5 off the 1dx values. Dock adjusted lens and -5 in camera and it works.

It adjusts the lens to match the camera its on.  That's what I was saying.  It then can be close, or way off on a different camera.  It depends on the actual adjustment accuracy of the camera you adjust it to.
 
I had a new 35mmL that was -2 on my 5D MK II but +17 on my 1D MK III.  Canon adjusted it for me, and it was right-on for both, and also at 0 AFMA when I upgraded to a 5D MK III.  I never could understand that. 
 
At plus five for the 5D MK III, that's fine.  But, if the lens changes over time, as some suggest, you have to recalibrate everything.

Yeah, but it's the same with a 35 L like you mention or the 50 Art or any other lens. The different afma values is about the lens , not the camera. And let's say my 50 misses with +20 at infinity, but that value works. And all the other values work, that's set in the lens. Now move it to a camera needing another +20 in general, that can be done. +20 in camera and +20 in lens. There's no difference in calibrating the 50 Art to a camera once the internal afma values are corresponding to each other. A camera doesn't really now what I set the 4 values to in my dock, and so it it's equal all over, only thing left to do is your normal afma. And as with any other lens, if it needs more than -+20, send it in.

And it seems clear that the drifting afma is with defective Sigma's,  bit the working ones.
Title: Re: Sigma 50mm Art 1.4 Focusing problems
Post by: Random Orbits on May 31, 2014, 06:32:38 AM
I have read lots and lots of threads here with people having AF problems with the 50A, but so far all of them had these issues with their 1D series camera, most notably the 1Dx.

Can someone confirm that these issues also affect other cameras as well?

IsaacImage also mentioned having difficulties on the 5DIII, which has a similar AF system.  Being able to nail thin DOF shots with outer focus points is such a advantage that I don't think I'm willing to go back to using centerpoint only (i.e. 5DII) even if the lens is superior.

Let's not forget that there are also people using a 5D MK III and do not have any problem with the 50Art. Mine works great. Couldn't be happier.
Just for the record, works great on my 6D too.

Yes, so it could be firmware dependent, or depend on some other settings in the camera.  Face it, it is more likely that all the lenses are the same, and that they are not having a QC issue and that there is something hokey in their reverse engineered software that does NOT work for every combination.
Title: Re: Sigma 50mm Art 1.4 Focusing problems
Post by: YuengLinger on May 31, 2014, 08:35:16 AM
As far as firmware in the cameras go, remember a recent update to the 5DIII that resulted in aftermarket batteries not registering properly?  Not showing charge remaining?

In fact, the charger that comes with the latest 5DIII's apparently had a similar "fix," where they won't even charge aftermarket batteries that were made prior to the firmware update.  You just get a rapidly blinking light no matter how often you fool with removing, unplugging, etc.  Same batteries in older chargers work fine.

So, ok, despite my skepticism, I do see the likelihood of a big corporation like Canon protectively taking steps to make AF hard as heck for independent lens makers.

And, IssacImage, by the way, I should have mentioned how great your photography is, despite my "suggestions" regarding your blogging.  Beautiful images, consistently.

Title: Re: Sigma 50mm Art 1.4 Focusing problems
Post by: Sella174 on May 31, 2014, 09:14:31 AM
The lens must give a camera a Canon lens code, and then the camera applies corrections and limitations based on a data table in the camera, so different camera generations might have some issues.

Is this true? Then that would explain the difficulties I had with the 40mm STM on my old cameras ...  :D
Title: Re: Sigma 50mm Art 1.4 Focusing problems
Post by: IsaacImage on May 31, 2014, 09:19:37 AM
The lens must give a camera a Canon lens code, and then the camera applies corrections and limitations based on a data table in the camera, so different camera generations might have some issues.

Is this true? Then that would explain the difficulties I had with the 40mm STM on my old cameras ...  :D

Appreciate this
Title: Re: Sigma 50mm Art 1.4 Focusing problems
Post by: Viggo on May 31, 2014, 01:12:03 PM
Yeah, but it's the same with a 35 L like you mention or the 50 Art or any other lens. The different afma values is about the lens , not the camera. And let's say my 50 misses with +20 at infinity, but that value works. And all the other values work, that's set in the lens. Now move it to a camera needing another +20 in general, that can be done. +20 in camera and +20 in lens. There's no difference in calibrating the 50 Art to a camera once the internal afma values are corresponding to each other. A camera doesn't really now what I set the 4 values to in my dock, and so it it's equal all over, only thing left to do is your normal afma. And as with any other lens, if it needs more than -+20, send it in.

The AFMA value is a product of the camera and lens.

Tiny changes in how the camera is manufactured (the sensor being half a mm closer or further away from the lens mount, for example) can also impact the AFMA value. It isn't just the lens and the variability in where the glass is within the lens relative to the mount on the back.

If it were only the lens then every camera would have the same AFMA value for any given lens and it doesn't work like that.

Not what I meant either. The four different distance afma settings you set in the new sigma lenses with the docking are there no matter what camera you mount it to. So if it's front focusing at 0,7 meters, dead on at 0,4m and for example back focus on infinity, that relationship will be the same no matter what the needed afma is. And that means when it's adjusted to hit at all those four distances, you can offset the entire range by using in camera afma, but not affect those four afma settings in camera at all. So it's not very important to which body you adjust those settings to, as long as it hits focus at every distance with that body. Changr body and do a normal afma in camera and still works withouy you ever knowing what the afma values at those four distances was set to.
Title: Re: Sigma 50mm Art 1.4 Focusing problems
Post by: longdrive70 on June 01, 2014, 02:00:06 PM
I am happy to report my "first batch" copy is performing perfect! 5,000 captures an no variation noticed on the autofocus.  ;D
Title: Re: Sigma 50mm Art 1.4 Focusing problems
Post by: Shane1.4 on June 01, 2014, 03:03:43 PM
Zero issues with it on my 5dmkiii or 6d.
Title: Re: Sigma 50mm Art 1.4 Focusing problems
Post by: Viggo on June 01, 2014, 07:22:41 PM
Mine is still going strong also.  :D
Title: Re: Sigma 50mm Art 1.4 Focusing problems
Post by: Viggo on June 03, 2014, 02:41:28 AM
Mine seems to have a very consistent front focusing issue with the two outermost points on each side of the frame. It appeared sharp when out in the sun, kind of hard to properly see the screen, but when I saw them on my computer a whole day of front focused pictures. I like to use the two outer points to frame vertically with my kids, but I say 95% is slightly front focused .

If I use center point it's extremely accurate and sharp. So Sigma, how do you adjust for that?

*edit* looks like going back to my old setup with the 4 point expansion helps a great deal with the outer points, along with Case 2 for static objects. This lens is VERY sharp wide open in the corners.

It's a real shame with the poor quality control that has always plagued Sigma is still there. But get a great copy and you have an EPIC lens.
Title: Re: Sigma 50mm Art 1.4 Focusing problems
Post by: YuengLinger on June 03, 2014, 06:03:43 AM
Viggo, those of us still waiting appreciate your updates, and this latest, how you try different AF settings for better results,  is another helpful one.

I think the strongest selling point of this lens for me is its sharpness across the frame, so being able to compose with at least any of the 5DIII's cross-points is an essential part of how I imagine using it.  Hopefully this won't be just a dream as AF issues get addressed...
Title: Re: Sigma 50mm Art 1.4 Focusing problems
Post by: Viggo on June 03, 2014, 06:23:12 AM
Viggo, those of us still waiting appreciate your updates, and this latest, how you try different AF settings for better results,  is another helpful one.

I think the strongest selling point of this lens for me is its sharpness across the frame, so being able to compose with at least any of the 5DIII's cross-points is an essential part of how I imagine using it.  Hopefully this won't be just a dream as AF issues get addressed...

You can't really trust the two outer points on each side, the one next to center is okay, but only center is fully trusted. And that kind of defeats the purpose of corner sharpness... The 85 L keeps delivering at any AF point...
Title: Re: Sigma 50mm Art 1.4 Focusing problems
Post by: wickidwombat on June 03, 2014, 06:26:47 AM
Viggo, those of us still waiting appreciate your updates, and this latest, how you try different AF settings for better results,  is another helpful one.

I think the strongest selling point of this lens for me is its sharpness across the frame, so being able to compose with at least any of the 5DIII's cross-points is an essential part of how I imagine using it.  Hopefully this won't be just a dream as AF issues get addressed...

You can't really trust the two outer points on each side, the one next to center is okay, but only center is fully trusted. And that kind of defeats the purpose of corner sharpness... The 85 L keeps delivering at any AF point...

I've found the 5 center column double cross types all perform equally well, with the very outer points also seem off sometimes but if i only use cross type points performance is good still
Title: Re: Sigma 50mm Art 1.4 Focusing problems
Post by: GMCPhotographics on June 03, 2014, 06:34:36 AM
Viggo, those of us still waiting appreciate your updates, and this latest, how you try different AF settings for better results,  is another helpful one.

I think the strongest selling point of this lens for me is its sharpness across the frame, so being able to compose with at least any of the 5DIII's cross-points is an essential part of how I imagine using it.  Hopefully this won't be just a dream as AF issues get addressed...

You can't really trust the two outer points on each side, the one next to center is okay, but only center is fully trusted. And that kind of defeats the purpose of corner sharpness... The 85 L keeps delivering at any AF point...

I'm sorry to hear that Viggo, but with a Sigma lens it really doesn't suprise me. Been there, done that and bought and sold many of these Tee shirts.....as i've said before, the 120-300 f2.8 OS was the last straw for me. Hey, I've even sold my 12-24mm recently too. I'm now Sigma free.
Title: Re: Sigma 50mm Art 1.4 Focusing problems
Post by: Viggo on June 03, 2014, 06:38:37 AM
Viggo, those of us still waiting appreciate your updates, and this latest, how you try different AF settings for better results,  is another helpful one.

I think the strongest selling point of this lens for me is its sharpness across the frame, so being able to compose with at least any of the 5DIII's cross-points is an essential part of how I imagine using it.  Hopefully this won't be just a dream as AF issues get addressed...

You can't really trust the two outer points on each side, the one next to center is okay, but only center is fully trusted. And that kind of defeats the purpose of corner sharpness... The 85 L keeps delivering at any AF point...

I've found the 5 center column double cross types all perform equally well, with the very outer points also seem off sometimes but if i only use cross type points performance is good still

I very rarely use upper an lower in the center, but as they are the same I guess you're right about that.

If I have the time to try spot, single point, and
4 point expansion and 6-7 shots to get the shot
I will get it. But using an outer point for a portrait mode shot and I have only one chance, it's usually off.
Title: Re: Sigma 50mm Art 1.4 Focusing problems
Post by: wickidwombat on June 03, 2014, 07:39:29 AM
Viggo, those of us still waiting appreciate your updates, and this latest, how you try different AF settings for better results,  is another helpful one.

I think the strongest selling point of this lens for me is its sharpness across the frame, so being able to compose with at least any of the 5DIII's cross-points is an essential part of how I imagine using it.  Hopefully this won't be just a dream as AF issues get addressed...

You can't really trust the two outer points on each side, the one next to center is okay, but only center is fully trusted. And that kind of defeats the purpose of corner sharpness... The 85 L keeps delivering at any AF point...

I've found the 5 center column double cross types all perform equally well, with the very outer points also seem off sometimes but if i only use cross type points performance is good still

I very rarely use upper an lower in the center, but as they are the same I guess you're right about that.

If I have the time to try spot, single point, and
4 point expansion and 6-7 shots to get the shot
I will get it. But using an outer point for a portrait mode shot and I have only one chance, it's usually off.
are you talking about the outer most points or the outer most cross type is you make only cross type selectable?
have you tried with only cross types selectable?
Title: Re: Sigma 50mm Art 1.4 Focusing problems
Post by: Viggo on June 03, 2014, 08:41:10 AM
Viggo, those of us still waiting appreciate your updates, and this latest, how you try different AF settings for better results,  is another helpful one.

I think the strongest selling point of this lens for me is its sharpness across the frame, so being able to compose with at least any of the 5DIII's cross-points is an essential part of how I imagine using it.  Hopefully this won't be just a dream as AF issues get addressed...

You can't really trust the two outer points on each side, the one next to center is okay, but only center is fully trusted. And that kind of defeats the purpose of corner sharpness... The 85 L keeps delivering at any AF point...

I've found the 5 center column double cross types all perform equally well, with the very outer points also seem off sometimes but if i only use cross type points performance is good still

I very rarely use upper an lower in the center, but as they are the same I guess you're right about that.

If I have the time to try spot, single point, and
4 point expansion and 6-7 shots to get the shot
I will get it. But using an outer point for a portrait mode shot and I have only one chance, it's usually off.
are you talking about the outer most points or the outer most cross type is you make only cross type selectable?
have you tried with only cross types selectable?

First thing I selected when I bought the 5d3 and the first thing I did when I got the 1dx, I always only use crosstype .
Title: Re: Sigma 50mm Art 1.4 Focusing problems
Post by: e-d0uble on June 18, 2014, 04:22:01 AM
I received my copy of this lens several days ago, and I admit that it's a bit of a head-scratcher for me.  First off, I ran a series of shots of a static target at different distances in order to calibrate it with the Sigma dock/optimization software.  I achieved razor sharp results at f/1.4 after dialing-in the appropriate adjustments for each distance on the scale.  I did use a tripod, an extremely bright halogen lamp (EV 10, at least), and center-point focus only for the calibration.  I also played around with live-view focus which obviously achieved excellent quality and consistent results.  After calibrating with the dock (each zone, save for infinity ended up at approximately +10 or so) I took the lens out for some test shots.  The results were somewhat inconsistent, as others on this forum have reported.  Many shots were spot-on, but some were confusingly out of focus - and often by a quite a wide margin.  I deliberately kept the lens at f/1.4, but made sure shutter speeds were never below 1/200th.  I probably should have noted what points on the 5d3 I was using when the misfocused shots were taken as I believe I did read a post on this forum that mentioned problems with off-center (or perhaps non-cross-type) focus points and this lens.

Next up, I attempted to AFMA with FoCal for kicks.  FoCal's AFMA module absolutely hated this lens and reported 'poor' confidence (red color) in two complete runs.  I didn't bother saving the logs.  Next up I used the FoCal's AF consistency module which reported 97.5% consistency with phase detection... weird.  I wonder if I've not received a dud lens, or if my old hands are shakier than I truly realize.  I do own the Sigma 35mm f/1.4A which is an absolute gem.  I have no problems whatsoever with the 35A in terms of auto focus.  Sure, 35mm has lots more DOF at F/1.4, but I just can't miss with it. 
Thoughts, anyone?  I see that some people have already exchanged their copies of the 50A (even several times)... Thanks.
Title: Re: Sigma 50mm Art 1.4 Focusing problems
Post by: IsaacImage on June 19, 2014, 12:56:26 AM
I received my copy of this lens several days ago, and I admit that it's a bit of a head-scratcher for me.  First off, I ran a series of shots of a static target at different distances in order to calibrate it with the Sigma dock/optimization software.  I achieved razor sharp results at f/1.4 after dialing-in the appropriate adjustments for each distance on the scale.  I did use a tripod, an extremely bright halogen lamp (EV 10, at least), and center-point focus only for the calibration.  I also played around with live-view focus which obviously achieved excellent quality and consistent results.  After calibrating with the dock (each zone, save for infinity ended up at approximately +10 or so) I took the lens out for some test shots.  The results were somewhat inconsistent, as others on this forum have reported.  Many shots were spot-on, but some were confusingly out of focus - and often by a quite a wide margin.  I deliberately kept the lens at f/1.4, but made sure shutter speeds were never below 1/200th.  I probably should have noted what points on the 5d3 I was using when the misfocused shots were taken as I believe I did read a post on this forum that mentioned problems with off-center (or perhaps non-cross-type) focus points and this lens.

Next up, I attempted to AFMA with FoCal for kicks.  FoCal's AFMA module absolutely hated this lens and reported 'poor' confidence (red color) in two complete runs.  I didn't bother saving the logs.  Next up I used the FoCal's AF consistency module which reported 97.5% consistency with phase detection... weird.  I wonder if I've not received a dud lens, or if my old hands are shakier than I truly realize.  I do own the Sigma 35mm f/1.4A which is an absolute gem.  I have no problems whatsoever with the 35A in terms of auto focus.  Sure, 35mm has lots more DOF at F/1.4, but I just can't miss with it. 
Thoughts, anyone?  I see that some people have already exchanged their copies of the 50A (even several times)... Thanks.

Sorry to hear that dear friend.
Looks like Sigma still trying to figure out the 5d mkiii/1dx AF system.
And it's very sad that still no words or any firmware update from Sigma yet.
Also the service guys still have no idea what to do with those issues.
Otherwise it's a great lens ;)

 
Title: Re: Sigma 50mm Art 1.4 Focusing problems
Post by: Eldar on June 19, 2014, 02:39:40 AM
I received my copy of this lens several days ago, and I admit that it's a bit of a head-scratcher for me.  First off, I ran a series of shots of a static target at different distances in order to calibrate it with the Sigma dock/optimization software.  I achieved razor sharp results at f/1.4 after dialing-in the appropriate adjustments for each distance on the scale.  I did use a tripod, an extremely bright halogen lamp (EV 10, at least), and center-point focus only for the calibration.  I also played around with live-view focus which obviously achieved excellent quality and consistent results.  After calibrating with the dock (each zone, save for infinity ended up at approximately +10 or so) I took the lens out for some test shots.  The results were somewhat inconsistent, as others on this forum have reported.  Many shots were spot-on, but some were confusingly out of focus - and often by a quite a wide margin.  I deliberately kept the lens at f/1.4, but made sure shutter speeds were never below 1/200th.  I probably should have noted what points on the 5d3 I was using when the misfocused shots were taken as I believe I did read a post on this forum that mentioned problems with off-center (or perhaps non-cross-type) focus points and this lens.

Next up, I attempted to AFMA with FoCal for kicks.  FoCal's AFMA module absolutely hated this lens and reported 'poor' confidence (red color) in two complete runs.  I didn't bother saving the logs.  Next up I used the FoCal's AF consistency module which reported 97.5% consistency with phase detection... weird.  I wonder if I've not received a dud lens, or if my old hands are shakier than I truly realize.  I do own the Sigma 35mm f/1.4A which is an absolute gem.  I have no problems whatsoever with the 35A in terms of auto focus.  Sure, 35mm has lots more DOF at F/1.4, but I just can't miss with it. 
Thoughts, anyone?  I see that some people have already exchanged their copies of the 50A (even several times)... Thanks.

Sorry to hear that dear friend.
Looks like Sigma still trying to figure out the 5d mkiii/1dx AF system.
And it's very sad that still no words or any firmware update from Sigma yet.
Also the service guys still have no idea what to do with those issues.
Otherwise it's a great lens ;)
I have lens no.2 now. The first was very unpredictable. This second one is more consistent, but not reliable. I have done both FoCal, with a mix of poor and acceptable results (The first lens did not pass FoCal at all) and a manual LensAlign test. With LensAlign I have found a fairly consistent back focus, coming from infinity to app. 1,2m and front focus coming from MFD. Not much, but enough to make f1.4 shots sufficiently out of focus to be annoying.

With the Eg-S focusing screen on the 5DIII and Ec-S on the 1DX, I get equal or better results shooting the Otus wide open. That sort of kills my interest in the Sigma ...

I agree on the optical performance though. When focus is right, you can get absolutely stunning images with this lens.
Title: Re: Sigma 50mm Art 1.4 Focusing problems
Post by: IsaacImage on June 19, 2014, 09:57:35 AM
I received my copy of this lens several days ago, and I admit that it's a bit of a head-scratcher for me.  First off, I ran a series of shots of a static target at different distances in order to calibrate it with the Sigma dock/optimization software.  I achieved razor sharp results at f/1.4 after dialing-in the appropriate adjustments for each distance on the scale.  I did use a tripod, an extremely bright halogen lamp (EV 10, at least), and center-point focus only for the calibration.  I also played around with live-view focus which obviously achieved excellent quality and consistent results.  After calibrating with the dock (each zone, save for infinity ended up at approximately +10 or so) I took the lens out for some test shots.  The results were somewhat inconsistent, as others on this forum have reported.  Many shots were spot-on, but some were confusingly out of focus - and often by a quite a wide margin.  I deliberately kept the lens at f/1.4, but made sure shutter speeds were never below 1/200th.  I probably should have noted what points on the 5d3 I was using when the misfocused shots were taken as I believe I did read a post on this forum that mentioned problems with off-center (or perhaps non-cross-type) focus points and this lens.

Next up, I attempted to AFMA with FoCal for kicks.  FoCal's AFMA module absolutely hated this lens and reported 'poor' confidence (red color) in two complete runs.  I didn't bother saving the logs.  Next up I used the FoCal's AF consistency module which reported 97.5% consistency with phase detection... weird.  I wonder if I've not received a dud lens, or if my old hands are shakier than I truly realize.  I do own the Sigma 35mm f/1.4A which is an absolute gem.  I have no problems whatsoever with the 35A in terms of auto focus.  Sure, 35mm has lots more DOF at F/1.4, but I just can't miss with it. 
Thoughts, anyone?  I see that some people have already exchanged their copies of the 50A (even several times)... Thanks.

Sorry to hear that dear friend.
Looks like Sigma still trying to figure out the 5d mkiii/1dx AF system.
And it's very sad that still no words or any firmware update from Sigma yet.
Also the service guys still have no idea what to do with those issues.
Otherwise it's a great lens ;)
I have lens no.2 now. The first was very unpredictable. This second one is more consistent, but not reliable. I have done both FoCal, with a mix of poor and acceptable results (The first lens did not pass FoCal at all) and a manual LensAlign test. With LensAlign I have found a fairly consistent back focus, coming from infinity to app. 1,2m and front focus coming from MFD. Not much, but enough to make f1.4 shots sufficiently out of focus to be annoying.

With the Eg-S focusing screen on the 5DIII and Ec-S on the 1DX, I get equal or better results shooting the Otus wide open. That sort of kills my interest in the Sigma ...

I agree on the optical performance though. When focus is right, you can get absolutely stunning images with this lens.

Thank you Eldar
Title: Re: Sigma 50mm Art 1.4 Focusing problems
Post by: GMCPhotographics on June 20, 2014, 07:54:24 AM
I received my copy of this lens several days ago, and I admit that it's a bit of a head-scratcher for me.  First off, I ran a series of shots of a static target at different distances in order to calibrate it with the Sigma dock/optimization software.  I achieved razor sharp results at f/1.4 after dialing-in the appropriate adjustments for each distance on the scale.  I did use a tripod, an extremely bright halogen lamp (EV 10, at least), and center-point focus only for the calibration.  I also played around with live-view focus which obviously achieved excellent quality and consistent results.  After calibrating with the dock (each zone, save for infinity ended up at approximately +10 or so) I took the lens out for some test shots.  The results were somewhat inconsistent, as others on this forum have reported.  Many shots were spot-on, but some were confusingly out of focus - and often by a quite a wide margin.  I deliberately kept the lens at f/1.4, but made sure shutter speeds were never below 1/200th.  I probably should have noted what points on the 5d3 I was using when the misfocused shots were taken as I believe I did read a post on this forum that mentioned problems with off-center (or perhaps non-cross-type) focus points and this lens.

Next up, I attempted to AFMA with FoCal for kicks.  FoCal's AFMA module absolutely hated this lens and reported 'poor' confidence (red color) in two complete runs.  I didn't bother saving the logs.  Next up I used the FoCal's AF consistency module which reported 97.5% consistency with phase detection... weird.  I wonder if I've not received a dud lens, or if my old hands are shakier than I truly realize.  I do own the Sigma 35mm f/1.4A which is an absolute gem.  I have no problems whatsoever with the 35A in terms of auto focus.  Sure, 35mm has lots more DOF at F/1.4, but I just can't miss with it. 
Thoughts, anyone?  I see that some people have already exchanged their copies of the 50A (even several times)... Thanks.

Sorry to hear that dear friend.
Looks like Sigma still trying to figure out the 5d mkiii/1dx AF system.
And it's very sad that still no words or any firmware update from Sigma yet.
Also the service guys still have no idea what to do with those issues.
Otherwise it's a great lens ;)
I have lens no.2 now. The first was very unpredictable. This second one is more consistent, but not reliable. I have done both FoCal, with a mix of poor and acceptable results (The first lens did not pass FoCal at all) and a manual LensAlign test. With LensAlign I have found a fairly consistent back focus, coming from infinity to app. 1,2m and front focus coming from MFD. Not much, but enough to make f1.4 shots sufficiently out of focus to be annoying.

With the Eg-S focusing screen on the 5DIII and Ec-S on the 1DX, I get equal or better results shooting the Otus wide open. That sort of kills my interest in the Sigma ...

I agree on the optical performance though. When focus is right, you can get absolutely stunning images with this lens.

I'm a bit curious, how did you fit a Eg-s screen to a 5DIII? I didn't think they were interchangable?
Title: Re: Sigma 50mm Art 1.4 Focusing problems
Post by: YuengLinger on June 20, 2014, 08:50:10 AM
Page 373 of the 5DMkIII user manual states that the focusing screen is fixed. 

This was a compromise I made with misgivings, but, in fact, I find the focusing screen to be pretty darn close to the Eg-S--and not as dark. 

Still, I do wish we had options.
Title: Re: Sigma 50mm Art 1.4 Focusing problems
Post by: GMCPhotographics on June 20, 2014, 08:59:11 AM
Page 373 of the 5DMkIII user manual states that the focusing screen is fixed. 

This was a compromise I made with misgivings, but, in fact, I find the focusing screen to be pretty darn close the the Eg-S--and not as dark. 

Still, I do wish we had options.

I still have a mkII with an Eg-s and it's not even close. But with spot focus set, I don't really have any issues with the focus accuracy...but it was more reassuring when I could actually see my 85 f1.2 pop into focus than just relying on the AF to do it's job fully.
Title: Re: Sigma 50mm Art 1.4 Focusing problems
Post by: Eldar on June 20, 2014, 10:38:05 AM
I'm a bit curious, how did you fit a Eg-s screen to a 5DIII? I didn't think they were interchangable?
It is not a 100% fit, but it works. I have had it installed for some time now and it works very well with my Zeiss lenses. I looked at the following video first:
https://www.youtube.com/watch?v=H1xUyqQNlys (https://www.youtube.com/watch?v=H1xUyqQNlys)

I have also used it with some of the L-lenses and AF works fine, with regular AFMA. You´ll have to adjust exposure about 2/3 stops, which means that auto-ISO does not work very well.
Title: Re: Sigma 50mm Art 1.4 Focusing problems
Post by: wickidwombat on June 21, 2014, 08:23:49 AM
I received my copy of this lens several days ago, and I admit that it's a bit of a head-scratcher for me.  First off, I ran a series of shots of a static target at different distances in order to calibrate it with the Sigma dock/optimization software.  I achieved razor sharp results at f/1.4 after dialing-in the appropriate adjustments for each distance on the scale.  I did use a tripod, an extremely bright halogen lamp (EV 10, at least), and center-point focus only for the calibration.  I also played around with live-view focus which obviously achieved excellent quality and consistent results.  After calibrating with the dock (each zone, save for infinity ended up at approximately +10 or so) I took the lens out for some test shots.  The results were somewhat inconsistent, as others on this forum have reported.  Many shots were spot-on, but some were confusingly out of focus - and often by a quite a wide margin.  I deliberately kept the lens at f/1.4, but made sure shutter speeds were never below 1/200th.  I probably should have noted what points on the 5d3 I was using when the misfocused shots were taken as I believe I did read a post on this forum that mentioned problems with off-center (or perhaps non-cross-type) focus points and this lens.

Next up, I attempted to AFMA with FoCal for kicks.  FoCal's AFMA module absolutely hated this lens and reported 'poor' confidence (red color) in two complete runs.  I didn't bother saving the logs.  Next up I used the FoCal's AF consistency module which reported 97.5% consistency with phase detection... weird.  I wonder if I've not received a dud lens, or if my old hands are shakier than I truly realize.  I do own the Sigma 35mm f/1.4A which is an absolute gem.  I have no problems whatsoever with the 35A in terms of auto focus.  Sure, 35mm has lots more DOF at F/1.4, but I just can't miss with it. 
Thoughts, anyone?  I see that some people have already exchanged their copies of the 50A (even several times)... Thanks.

Sorry to hear that dear friend.
Looks like Sigma still trying to figure out the 5d mkiii/1dx AF system.
And it's very sad that still no words or any firmware update from Sigma yet.
Also the service guys still have no idea what to do with those issues.
Otherwise it's a great lens ;)
I have lens no.2 now. The first was very unpredictable. This second one is more consistent, but not reliable. I have done both FoCal, with a mix of poor and acceptable results (The first lens did not pass FoCal at all) and a manual LensAlign test. With LensAlign I have found a fairly consistent back focus, coming from infinity to app. 1,2m and front focus coming from MFD. Not much, but enough to make f1.4 shots sufficiently out of focus to be annoying.

With the Eg-S focusing screen on the 5DIII and Ec-S on the 1DX, I get equal or better results shooting the Otus wide open. That sort of kills my interest in the Sigma ...

I agree on the optical performance though. When focus is right, you can get absolutely stunning images with this lens.

you HAVE to adjust it with the dock, focal and in body AFMA is half the problem you guys are having. seriously...
Title: Re: Sigma 50mm Art 1.4 Focusing problems
Post by: YuengLinger on June 21, 2014, 10:56:28 AM
Too bad Sigma has not been able to satisfy the pickiest photographers on the planet yet.  I'm hopeful but will return it if AF not as good as on my 35 Art.  After that, only clear evidence of a fix could induce me to try again.
Title: Re: Sigma 50mm Art 1.4 Focusing problems
Post by: playaz on July 02, 2014, 05:31:13 PM
I got the 50A today and took some quick photos. Seems like it is front focusing a bit but will do further tests tomororow under better light to be sure.

I was wondering what is the best way to do the most accurate tests to figure out how much it is front/back focusing at different focus distance and then how to adjust them in the Sigma USB dock I purchased as well?
Title: Re: Sigma 50mm Art 1.4 Focusing problems
Post by: Viggo on July 03, 2014, 05:00:59 AM
I got the 50A today and took some quick photos. Seems like it is front focusing a bit but will do further tests tomororow under better light to be sure.

I was wondering what is the best way to do the most accurate tests to figure out how much it is front/back focusing at different focus distance and then how to adjust them in the Sigma USB dock I purchased as well?

Reikan Focal. Or if you want a cheaper setup, use a nice bright white lamp and place a big checkerboard parallel to the sensor at 0,4m 0,7m 3.5m and as long as doable. Take a LV focused shot, and/or manual and start shooting and using the in camera afma until you match the manually focused sharpness with phase AF. And note that value and do the next distance. When you're done you will have 4 afma values you plot in to the lens via docking. Make sure to shoot at least 5-10 shots pr distance and pull focus way off between shots.
Title: Re: Sigma 50mm Art 1.4 Focusing problems
Post by: playaz on July 03, 2014, 06:01:41 AM
I can't do Focal because my DSLR is not supported there and no micro-adjustment as well.

So I started doing tests on a printed chart at 0.4m and adjusting in DOCK by +1. Does the dock + 5 seems ok to you too or shall I keep going further?

(http://oi62.tinypic.com/zmm8fs.jpg)

(http://oi59.tinypic.com/acqy2q.jpg)

(http://oi59.tinypic.com/2m6486x.jpg)

(http://oi62.tinypic.com/2djwbhk.jpg)

(http://oi59.tinypic.com/2m6srcp.jpg)

(http://oi62.tinypic.com/ct35x.jpg)
Title: Re: Sigma 50mm Art 1.4 Focusing problems
Post by: Mika on July 03, 2014, 08:08:46 AM
Quote
I have lens no.2 now. The first was very unpredictable. This second one is more consistent, but not reliable. I have done both FoCal, with a mix of poor and acceptable results (The first lens did not pass FoCal at all) and a manual LensAlign test. With LensAlign I have found a fairly consistent back focus, coming from infinity to app. 1,2m and front focus coming from MFD. Not much, but enough to make f1.4 shots sufficiently out of focus to be annoying.

With the Eg-S focusing screen on the 5DIII and Ec-S on the 1DX, I get equal or better results shooting the Otus wide open. That sort of kills my interest in the Sigma ...

I agree on the optical performance though. When focus is right, you can get absolutely stunning images with this lens.

I have it reversed on 5D. From INF to 2 metres, front focusing.
From MFD to 2 metres, back focus. The lens is now sent to service, from what it seems to me, this looks like a software thing. I suspect there's nothing wrong in the lens mechanics itself.

Given the images I got with it, I'm willing to wait a couple of months to get the software ironed out. But photography is indeed not my day job and I can see why this would not be acceptable for pros. Sigma 50 Art is still the best 50/1.4 I've seen image quality-wise, background or punch.
Title: Re: Sigma 50mm Art 1.4 Focusing problems
Post by: Eldar on July 04, 2014, 03:12:00 AM
you HAVE to adjust it with the dock, focal and in body AFMA is half the problem you guys are having. seriously...
I have used all available adjustment options, but that is not the issue. The issue is inconsistency. The dock and in camera AFMA will help you adjust a consistent focus deviation. My problem, and apparently a few others, is inconsistent focusing. There is no available adjustment aid for that.
Title: Re: Sigma 50mm Art 1.4 Focusing problems
Post by: Mika on July 11, 2014, 08:04:49 AM
A short update:

I got my 50A back from the shop, and lo and behold, the inconsistency was gone. Sigma representative said they adjusted the lens to a standard body, and then returned it. Now the lens was back focusing either when approached from INF or MFD, which is OK from my books as I've tools to correct that. So Sigma dock it is, and 20 mins of adjustments later, I was ready for real life testing.

In the 300 photos I took last evening, I didn't see focus errors, and got a very good keeper ratio. The lens is now working, and actually seems to be sharp enough that I actually need to decrease camera sharpening preset for JPEGs.

EDIT: I'll have to say that this lens rocks! The background blur stopped down is a definite improvement over Canon's 50/1.4!
Title: Re: Sigma 50mm Art 1.4 Focusing problems
Post by: GMCPhotographics on July 11, 2014, 11:23:27 AM
A short update:

I got my 50A back from the shop, and lo and behold, the inconsistency was gone. Sigma representative said they adjusted the lens to a standard body, and then returned it. Now the lens was back focusing either when approached from INF or MFD, which is OK from my books as I've tools to correct that. So Sigma dock it is, and 20 mins of adjustments later, I was ready for real life testing.

In the 300 photos I took last evening, I didn't see focus errors, and got a very good keeper ratio. The lens is now working, and actually seems to be sharp enough that I actually need to decrease camera sharpening preset for JPEGs.

EDIT: I'll have to say that this lens rocks! The background blur stopped down is a definite improvement over Canon's 50/1.4!

Yep, it's great idea of Sigma's...make an expensive device to get customers to do their work for them.
You pay Sigma to spend you time correcting their sloppy manufacturing errors. Maybe Ford should make cars which only drive properly after you buy their laptop software to interface with it....
Title: Re: Sigma 50mm Art 1.4 Focusing problems
Post by: mrsfotografie on July 11, 2014, 11:48:48 AM
A short update:

I got my 50A back from the shop, and lo and behold, the inconsistency was gone. Sigma representative said they adjusted the lens to a standard body, and then returned it. Now the lens was back focusing either when approached from INF or MFD, which is OK from my books as I've tools to correct that. So Sigma dock it is, and 20 mins of adjustments later, I was ready for real life testing.

In the 300 photos I took last evening, I didn't see focus errors, and got a very good keeper ratio. The lens is now working, and actually seems to be sharp enough that I actually need to decrease camera sharpening preset for JPEGs.

EDIT: I'll have to say that this lens rocks! The background blur stopped down is a definite improvement over Canon's 50/1.4!

Yep, it's great idea of Sigma's...make an expensive device to get customers to do their work for them.
You pay Sigma to spend you time correcting their sloppy manufacturing errors. Maybe Ford should make cars which only drive properly after you buy their laptop software to interface with it....

Actually I know of some people who fiddle with their car's engine management using... a laptop.
Title: Re: Sigma 50mm Art 1.4 Focusing problems
Post by: Mika on July 11, 2014, 12:35:44 PM
Quote
Yep, it's great idea of Sigma's...make an expensive device to get customers to do their work for them.
You pay Sigma to spend you time correcting their sloppy manufacturing errors. Maybe Ford should make cars which only drive properly after you buy their laptop software to interface with it....

Why? It isn't like the Canon objectives themselves wouldn't require work from the owner when it comes to AFMA.

So, I knew I was getting a lens from the first batch. I knew glitches are sort of inevitable with each new product introduction. Then again, it's about my private time valuation. 20 minutes of playing with the dock, and I got a much better lens for 800 €. I never had problems with 35A, or their other lenses. And it's much better than Canon's 50/1.4, and more general purpose than 50/1.0, exactly what I wanted.

Now I wish I could do the same adjustment with Canon's 70-200/4 IS and my 5D. That objective performs well on my 40D, but is not that stellar with 5D...
Title: Re: Sigma 50mm Art 1.4 Focusing problems
Post by: Viggo on July 11, 2014, 01:43:25 PM
A short update:

I got my 50A back from the shop, and lo and behold, the inconsistency was gone. Sigma representative said they adjusted the lens to a standard body, and then returned it. Now the lens was back focusing either when approached from INF or MFD, which is OK from my books as I've tools to correct that. So Sigma dock it is, and 20 mins of adjustments later, I was ready for real life testing.

In the 300 photos I took last evening, I didn't see focus errors, and got a very good keeper ratio. The lens is now working, and actually seems to be sharp enough that I actually need to decrease camera sharpening preset for JPEGs.

EDIT: I'll have to say that this lens rocks! The background blur stopped down is a definite improvement over Canon's 50/1.4!

Yep, it's great idea of Sigma's...make an expensive device to get customers to do their work for them.
You pay Sigma to spend you time correcting their sloppy manufacturing errors. Maybe Ford should make cars which only drive properly after you buy their laptop software to interface with it....

Lol, like a laptop can fix a Ford  ;D
Title: Re: Sigma 50mm Art 1.4 Focusing problems
Post by: IsaacImage on July 12, 2014, 11:21:01 AM
A short update:

I got my 50A back from the shop, and lo and behold, the inconsistency was gone. Sigma representative said they adjusted the lens to a standard body, and then returned it. Now the lens was back focusing either when approached from INF or MFD, which is OK from my books as I've tools to correct that. So Sigma dock it is, and 20 mins of adjustments later, I was ready for real life testing.

In the 300 photos I took last evening, I didn't see focus errors, and got a very good keeper ratio. The lens is now working, and actually seems to be sharp enough that I actually need to decrease camera sharpening preset for JPEGs.

EDIT: I'll have to say that this lens rocks! The background blur stopped down is a definite improvement over Canon's 50/1.4!

Yep, it's great idea of Sigma's...make an expensive device to get customers to do their work for them.
You pay Sigma to spend you time correcting their sloppy manufacturing errors. Maybe Ford should make cars which only drive properly after you buy their laptop software to interface with it....

Lol, like a laptop can fix a Ford  ;D

Nice idea ;)
Title: Re: Sigma 50mm Art 1.4 Focusing problems
Post by: YuengLinger on July 15, 2014, 09:59:24 AM
Well, I got mine, and...Darn, the AF is whacky.

Works fine up to about 5', but definitely front focuses badly beyond that--a good part of the time.  Not always!

I did an in-camera AFMA with my 5DIII, hoping that would be all I needed, as it looked great at the tested distance.  But as soon as I got outdoors, the inconsistency started.

I did not order the dock with the lens, as I had great luck with the 35mm Art.  I do like the lens when it works, but I don't know that it is worth more ordering, testing, adjusting...

Seriously considering just returning the thing. 

Thanks to all who have posted their ups and downs with this much hyped, much desired lens!

ALSO:  I do get the impression that, for some reason, I can "help" the AF by doing an AE lock on the targeted area that I want to focus on.  How could this be on a 5D3?  Seems to work too often to be just my imagination...
Title: Re: Sigma 50mm Art 1.4 Focusing problems
Post by: YuengLinger on July 15, 2014, 11:13:07 AM
UPDATE

To help with the decision making process, whether to keep or ship back the 50 Art, I called Sigma Tech Support.  Got right through.  Yes, they recommend the dock, but the surprising bit I heard was a vehement denial that Sigma "reverse engineers" their AF systems.  The tech said that "Japan is a socialist nation, and they don't keep these things secret.  Sigma works with Canon.  We get our specs from Canon.  Anything other than this is internet fantasy."

He also went onto say that the 50mm Art is a "reverse telephoto...a VERY TOUCHY type of lens."  This as an explanation for why the dock is so important.

Had a photo session this morning, using my ef 24-70mm 2.8 II.  How wonderful to hit the focus every time, not worry.

Sigh...
Title: Re: Sigma 50mm Art 1.4 Focusing problems
Post by: Viggo on July 15, 2014, 11:22:17 AM
YuengLinger: I have a swedish friend who also got the 35 Art and 50 Art the other day, his 35 works flawless and is everything it should be, whilst the 50 is all over. I had the opposite experience and I had two 35's and two 50's, only one out of those 4 worked at all, and I have the docking.

Conclusion is, Sigma just can't do proper QC, it's just to many that doesn't work.... Lucikly I got a peeerfect 50 Art the second time.
Title: Re: Sigma 50mm Art 1.4 Focusing problems
Post by: NancyP on July 15, 2014, 11:46:52 AM
I seriously doubt that Canon shares ALL of the details of autofocus protocols with Sigma. I am sure that Canon shares the basic protocols, but the tweaks made to adapt each motor- lens-AF protocol unit would not be given to Sigma, and in fact would not be pertinent. Sigma has to work out conditions for its own motor-lens combos. Canon may not have shared any of the AF protocols (and other lens communications, involving aperture stop-down) earlier on, given that there are Sigma lenses out there that will not function on newer Canon bodies.

I hardly think of Japan as "socialist". What baloney. American capitalists have learned a thing or two from Japanese businesses regarding production and innovation. A major difference is that the Japanese government openly supports early stage R and D, whereas the U.S. government hides its support of early R and D under a complicated grants and contracts system that doesn't get seen by the average citizen.
Title: Re: Sigma 50mm Art 1.4 Focusing problems
Post by: mrsfotografie on July 15, 2014, 11:48:58 AM
YuengLinger: I have a swedish friend who also got the 35 Art and 50 Art the other day, his 35 works flawless and is everything it should be, whilst the 50 is all over. I had the opposite experience and I had two 35's and two 50's, only one out of those 4 worked at all, and I have the docking.

Conclusion is, Sigma just can't do proper QC, it's just to many that doesn't work.... Lucikly I got a peeerfect 50 Art the second time.

Ok I'm sticking to my 35A and 50 EX, both are truly excellent copies (yes my 50 is spot on most of the time too).
Title: Re: Sigma 50mm Art 1.4 Focusing problems
Post by: YuengLinger on July 15, 2014, 12:17:28 PM
Just got my RMA from B&H.  Simply don't want to deal with the dock.  Also, just read on the lensrental site that they have had "multiple" problems with the lens locking up during adjustment on the dock.

And I don't play the "good copy" game.

Lovely bokeh, all around IQ, but I'm too spoiled by AF to give it up for MF!   :-X
Title: Re: Sigma 50mm Art 1.4 Focusing problems
Post by: GammyKnee on July 15, 2014, 12:48:22 PM
Conclusion is, Sigma just can't do proper QC, it's just to many that doesn't work.... Lucikly I got a peeerfect 50 Art the second time.

I wish I could find out what the odds are in this Sigma QC lottery, 'cos this new 50 is even more appealing than its predecessor (got burned by that one myself).

Has anybody checked serial/batch numbers to see if there's any trend, e.g. are newer production runs any better than earlier ones?

Title: Re: Sigma 50mm Art 1.4 Focusing problems
Post by: sdsr on July 15, 2014, 03:32:33 PM
Just got my RMA from B&H.  Simply don't want to deal with the dock.  Also, just read on the lensrental site that they have had "multiple" problems with the lens locking up during adjustment on the dock.

And I don't play the "good copy" game.

Lovely bokeh, all around IQ, but I'm too spoiled by AF to give it up for MF!   :-X

I expect that if I ever decide I want this lens I'll buy an EF mount but use it on my Sony A7r, where MF is easy. But it's annoying to buy a fairly expensive AF lens which you're expected to fiddle around with on a docking station and even then seems best used, in the case of many copies at any rate, in MF mode.  (Speaking of MF, I've recently been greatly enjoying a 50mm 1.4 Pentax/Takumar; excellent image quality, small, fairly light and, to these eyes, more attractive... and it just works.  All for c. $100.)
Title: Re: Sigma 50mm Art 1.4 Focusing problems
Post by: thestructured on July 21, 2014, 06:14:15 PM
I feel so much better to have read this thread. I registered with this forum just to share my experiences. I'm soon to be on my fourth copy of the sigma 50 art. Copy #1 had the issue where center point focusing was fine, however outer points resulted in front focusing, and this was consistent. AFMA can't fix that because it will result in the center cluster (5d3) not working properly. Same issues on my 6d, to a lesser degree. Sigma said they can't fix it until new firmware comes out that addresses this problem. Onto copy #2; my second copy had no problems. It was a beautiful thing, not only because the optics are phenomenal but because it confirmed that I'm not insane and imagining that the first copy had a problem. It was a night and day difference. Then, like an idiot, I returned the second one (the dealer I got it from was selling them at an inflated price) and picked a third one up elsewhere since I found them at their normal price (put $200 back in my pocket). Well, I now regret that because the third one has the same exact outer point issue as copy #1 did. I am going to try for a 4th one, though it's hard to play this game because they are not consistently in stock anywhere.

This problem is very real. If you're lucky enough to get a copy without issues, (and they DO exist), do. not. sell. it.

Title: Re: Sigma 50mm Art 1.4 Focusing problems
Post by: IsaacImage on July 22, 2014, 01:02:50 AM
I feel so much better to have read this thread. I registered with this forum just to share my experiences. I'm soon to be on my fourth copy of the sigma 50 art. Copy #1 had the issue where center point focusing was fine, however outer points resulted in front focusing, and this was consistent. AFMA can't fix that because it will result in the center cluster (5d3) not working properly. Same issues on my 6d, to a lesser degree. Sigma said they can't fix it until new firmware comes out that addresses this problem. Onto copy #2; my second copy had no problems. It was a beautiful thing, not only because the optics are phenomenal but because it confirmed that I'm not insane and imagining that the first copy had a problem. It was a night and day difference. Then, like an idiot, I returned the second one (the dealer I got it from was selling them at an inflated price) and picked a third one up elsewhere since I found them at their normal price (put $200 back in my pocket). Well, I now regret that because the third one has the same exact outer point issue as copy #1 did. I am going to try for a 4th one, though it's hard to play this game because they are not consistently in stock anywhere.

This problem is very real. If you're lucky enough to get a copy without issues, (and they DO exist), do. not. sell. it.

Sorry to hear that , but you brought me smile ;)
Yes, I remember that once I had great D800 without any AF points issues …. well almost .. well just the left one ;)
and I return it and got even worst one ;)
Title: Re: Sigma 50mm Art 1.4 Focusing problems
Post by: Viggo on July 22, 2014, 02:47:15 AM
...
But it's annoying to buy a fairly expensive AF lens which you're expected to fiddle around with on a docking station and even then seems best used, in the case of many copies at any rate, in MF mode.
...

Why do you think AFMA exists on Canon cameras? To address the same problem that the docking station is for.

The problem isn't QC it is engineering tolerances and the fact that neither camera nor lens are all made the same. There is copy variation between each camera and lens. This means that whilst AFMA might be +5 for a given lens on your camera, that same lens might be -5 on my camera and that same lens might be +0 on someone else's camera.

Like we've said soo many times before, it's NOT about afma ... Sigh, it's the  inconsistency ! Please print this message and tape it on your fridge.
Title: Re: Sigma 50mm Art 1.4 Focusing problems
Post by: fotonunta on July 22, 2014, 06:54:59 AM
All Sigma lenses have focusing problems! I had two of the a 24-700 and 70-200 last versions - I sent them to be calibrated with my body and then everything was ok.
Title: Re: Sigma 50mm Art 1.4 Focusing problems
Post by: rs on July 22, 2014, 07:23:17 AM
...
But it's annoying to buy a fairly expensive AF lens which you're expected to fiddle around with on a docking station and even then seems best used, in the case of many copies at any rate, in MF mode.
...

Why do you think AFMA exists on Canon cameras? To address the same problem that the docking station is for.

The problem isn't QC it is engineering tolerances and the fact that neither camera nor lens are all made the same. There is copy variation between each camera and lens. This means that whilst AFMA might be +5 for a given lens on your camera, that same lens might be -5 on my camera and that same lens might be +0 on someone else's camera.

Like we've said soo many times before, it's NOT about afma ... Sigh, it's the  inconsistency ! Please print this message and tape it on your fridge.

AFMA is there because there is inconsistency. Canon recognizes that there is inconsistency in camera/lens manufacture and thus introduced that feature to allow people to tune their own camera. If every lens was the same, AFMA wouldn't be needed.

AFMA is there for consistent errors. Inconsistent errors cannot be corrected with a simple offset.
Title: Re: Sigma 50mm Art 1.4 Focusing problems
Post by: YuengLinger on July 22, 2014, 07:25:49 AM
Dilbert, you are misunderstanding "inconsistency."

The 50 Art can be perfectly calibrated, yet still misses focus on too many shots. 

You get your AFMA perfect, then you get into a shooting situation, and one shot will be just right, then the next three will be terribly front or back focused.  I know--that is exactly why I sent mine back.

After trying for 10 days to get the 50 Art to function properly, I went back to using lenses that do work, such as the ef 85mm 1.2 L (so I know all about shallow DoF) and the ef 24-70mm 2.8 II L.  WHAT a FREAKING relief to have sharp, accurate, 95% successful AF!!!

Dilbert, do you understand now?  The 50 Art, for whatever reason, can be perfectly "tuned" to match a body, and still be all over the place.  If you happened to get a copy that does not exhibit such behavior, stop trying to tell others that there is some kind of user error or misunderstanding.

And, btw, I have a 35 Art that is almost as reliable with AF as my 24-70 (the best AF I've ever seen), and a Sigma 15mm 2.8 fisheye that is spectacular.  Those work.  I think I made a mistake buying the 50 Art before Sigma, using its customers as testers, figured out what is wrong with their production. 

As for the USB dock, it might make things worse for Sigma customers, because now there is this extra level of trouble-shooting Sigma tech support can use to delay actually finding out the true problems with their lenses.  Customer calls Sigma complaining about erratic AF, Sigma asks, "Have you used the dock?"  Customer buys dock, gets frustrated, return time to merchant has expired...Seems like it will cause more problems than it fixes FOR THOSE CUSTOMERs WHO KNOW HOW TO AFMA IN CAMERA. 
Title: Re: Sigma 50mm Art 1.4 Focusing problems
Post by: YuengLinger on July 22, 2014, 07:38:51 AM
All Sigma lenses have focusing problems! I had two of the a 24-700 and 70-200 last versions - I sent them to be calibrated with my body and then everything was ok.

This is FALSE.  I have two Sigma lenses that have had no focusing problems.  (I don't consider improving AF accuracy with in-camera AFMA to be part of a "problem.")

But the 50 Art that I received did have erratic, unreliable AF that could not be helped with AFMA.

So, if online chatter can lead to Sigma fixing the problem, we aren't helping by using sweeping, ranting statements such as "All Sigma lenses have focusing problems!"
Title: Re: Sigma 50mm Art 1.4 Focusing problems
Post by: infared on July 22, 2014, 08:02:50 AM
I have an original Sigma 5Omm f/1.4 and it focuses just fine on my 5DIII. Out of the box no adjustments.
I also own a Sigma 35mm Art  and it performed just fine right out of the box as well. No adjustments.
Title: Re: Sigma 50mm Art 1.4 Focusing problems
Post by: candyman on July 22, 2014, 08:19:36 AM
All Sigma lenses have focusing problems! I had two of the a 24-700 and 70-200 last versions - I sent them to be calibrated with my body and then everything was ok.

This is FALSE.  I have two Sigma lenses that have had no focusing problems.  (I don't consider improving AF accuracy with in-camera AFMA to be part of a "problem.")

But the 50 Art that I received did have erratic, unreliable AF that could not be helped with AFMA.

So, if online chatter can lead to Sigma fixing the problem, we aren't helping by using sweeping, ranting statements such as "All Sigma lenses have focusing problems!"

I stated this before and say this again: I did not and do not have AF problems with my 50Art. And I agree with YuengLinger.  It is wrong to make statements like "All Sigma lenses have focusing problems!" - it is not true. Sigma did a great job with the Art series.
Title: Re: Sigma 50mm Art 1.4 Focusing problems
Post by: neuroanatomist on July 22, 2014, 08:24:22 AM
I have never owned a Sigma lens with focusing problems.  But then...I've never owned a Sigma lens.  :P

I have tried a couple, and found the focus to be erratic on both. 

I think it's fair to say that some lenses have focus issues, across all brands.  The proportion of those problematic lenses does seem higher with Sigma.
Title: Re: Sigma 50mm Art 1.4 Focusing problems
Post by: sdsr on July 22, 2014, 10:29:53 AM
...
But it's annoying to buy a fairly expensive AF lens which you're expected to fiddle around with on a docking station and even then seems best used, in the case of many copies at any rate, in MF mode.
...

Why do you think AFMA exists on Canon cameras? To address the same problem that the docking station is for.

The problem isn't QC it is engineering tolerances and the fact that neither camera nor lens are all made the same. There is copy variation between each camera and lens. This means that whilst AFMA might be +5 for a given lens on your camera, that same lens might be -5 on my camera and that same lens might be +0 on someone else's camera.

I don't disagree with any of that (to the extent you're talking about AFMA adjustments rather than inconsistency).  My comment wasn't specifically about Sigma, though it seems more of their lenses need adjusting than others and more of them focus inconsistently within any given AFMA tweak.  But after using a variety of mirrorless cameras over the past 18 months, where AFMA simply isn't an issue, I'm getting less tolerant of/patient with this aspect of dslr technology.  As for inconsistency within any given AFMA adjustment, presumably mirrorless isn't helpful, but manual focusing avoids that and mirrorless cameras make manual focusing easy (I recently bought an EF-mount version of the excellent Sigma 70mm macro and have been using it on my A7r rather than my 5DIII - so no focusing problems at all aside from incompetence at my end...).
Title: Re: Sigma 50mm Art 1.4 Focusing problems
Post by: rs on July 22, 2014, 11:03:49 AM
All Sigma lenses have focusing problems! I had two of the a 24-700 and 70-200 last versions - I sent them to be calibrated with my body and then everything was ok.

This is FALSE.  I have two Sigma lenses that have had no focusing problems.  (I don't consider improving AF accuracy with in-camera AFMA to be part of a "problem.")

But the 50 Art that I received did have erratic, unreliable AF that could not be helped with AFMA.

So, if online chatter can lead to Sigma fixing the problem, we aren't helping by using sweeping, ranting statements such as "All Sigma lenses have focusing problems!"

I stated this before and say this again: I did not and do not have AF problems with my 50Art. And I agree with YuengLinger.  It is wrong to make statements like "All Sigma lenses have focusing problems!" - it is not true. Sigma did a great job with the Art series.

+1

My second copy of the Sigma 50/1.4 (non Art) focuses very accurately and consistently. The same can't be said of the first though  ::)
Title: Re: Sigma 50mm Art 1.4 Focusing problems
Post by: thestructured on July 22, 2014, 08:46:37 PM
I put in my order for a FOURTH sigma 50 art. Unfortunately, from 47th street photo who is selling them at an inflated price, but whatever, I don't care much about $100 difference IF I get a good, consistently working copy.

Back to my original post, where I said copy #2 was fine; it was fine in that all focus points were accurate unlike copy #1 and #3 where using any outer points results in front focusing- I just got done editing the first wedding I used #2 at and there are so many out of focus shots that it's embarrassing. I guess it wasn't a perfect copy after all. It seemed to have a particularly bad time with servo focusing. I hope sigma can make this all better with a firmware update.

And to those of you still talking about AFMA; the reason that won't help in this case is because the focus is only off when using outer focus points, and mostly accurate when using center points (I've found that any of the center cluster on the 5d3 works, not just the middle one). AFMA to fix the outer points will make the center points off. I've tried it on both, you cannot fix it.

Having said that, my sigma 35 art is very, very reliable. I love that friggen lens. Even servo focusing in the dark with outer 6d single orientation points consistently gives me in focus photos. It helps that the DOF at 35mm is greater than at 50mm, of course.

crossing my fingers for 50 art #4.....

for those of you that do not have problems, here are some files of center focus points vs outer ones. You can see the shift in focus to the front, and it's just enough to give you OOF photos.


 
Title: Re: Sigma 50mm Art 1.4 Focusing problems
Post by: YuengLinger on July 23, 2014, 09:52:20 AM
Based on seat of my pants calculations it seems like these lenses have a problem in about one out of three cases.  Does that seem fair?
Title: Re: Sigma 50mm Art 1.4 Focusing problems
Post by: mrsfotografie on July 23, 2014, 01:14:39 PM
I have an original Sigma 5Omm f/1.4 and it focuses just fine on my 5DIII. Out of the box no adjustments.
I also own a Sigma 35mm Art  and it performed just fine right out of the box as well. No adjustments.

+1
Title: Re: Sigma 50mm Art 1.4 Focusing problems
Post by: wickidwombat on July 24, 2014, 06:42:05 AM
Based on seat of my pants calculations it seems like these lenses have a problem in about one out of three cases.  Does that seem fair?

not really you are taking an extremely small sample group from an internet forum there are probably many many more buyers that dont come here who knows what their experiences are

got to love internet induced fear and mass hysteria....
Title: Re: Sigma 50mm Art 1.4 Focusing problems
Post by: neuroanatomist on July 24, 2014, 07:15:16 AM
Based on seat of my pants calculations it seems like these lenses have a problem in about one out of three cases.  Does that seem fair?

not really you are taking an extremely small sample group from an internet forum there are probably many many more buyers that dont come here who knows what their experiences are

True.  That's the problem with a small, non-representative sample size like CR forums.   For all we know, it could be that everyone in the world who has gotten a good Sigma lens is posting here, and 99.99% of lenses out there have problems.

 ;)
Title: Re: Sigma 50mm Art 1.4 Focusing problems
Post by: wickidwombat on July 24, 2014, 07:36:51 AM
Based on seat of my pants calculations it seems like these lenses have a problem in about one out of three cases.  Does that seem fair?

not really you are taking an extremely small sample group from an internet forum there are probably many many more buyers that dont come here who knows what their experiences are

True.  That's the problem with a small, non-representative sample size like CR forums.   For all we know, it could be that everyone in the world who has gotten a good Sigma lens is posting here, and 99.99% of lenses out there have problems.

 ;)

haha entirely possible ;)

I have 3 sigma lenses actually had 4 including the previous sigma 50 which i gave away after i got the art but it was pretty flakey on my bodies however it seemed fine on my wifes 5Dmk3 though...

the 85 which i love was my first and out of the box it was horribly back focusing the the degree of the 13 adjustment in AFMA, i sent it in to sigma and it was back in under week and was spot on i dont have that lens set to any AFMA value on any camera and its been used on 2 5Dmk2 bodies 2 5Dmk3 a 1Dmk3 a 600D a 550D and 2 different EOS-M bodies all are fine. it does however miss focus occasionally but not very often.

the 35 was perfect out of the box is amazing tracks so fast is incredibly accurate and just mindblowingly good it just never misses. EVER

the 50 ART was off and i knew it as soon as i picked it up in the store nut hey it was the first and only copy in china so i didnt have alot of choice, i bought the dock and calibrated it and it seems fine but it still misses sometimes but is FAR and away more reliable than the 50 1.4 canon or sigma old version or the 1.8 canon (I never bought the 1.2 but tried it many times and never could feel it was worth the price)
after calibration the 50 ART is pretty great and I've been using it alot its an amazing piece of glass especially considering the price.

So while i'm a fan of sigma primes I full agree that they definitely have a high frequency of issues out of the box but with some perseverance these can be fixed.
Title: Re: Sigma 50mm Art 1.4 Focusing problems
Post by: gruhl28 on July 24, 2014, 12:02:34 PM
Since it is the camera that determines whether something is in focus or not, can someone explain to me how it is that some lenses could focus inconsistently but others focus consistently on the same camera body? I can understand the need for AFMA if the focus sensor isn't in the same plane as the image sensor, but how can there be inconsistency with some lenses and not others?
Title: Re: Sigma 50mm Art 1.4 Focusing problems
Post by: Stephen Melvin on July 24, 2014, 01:46:03 PM
Back when I was shooting APS format cameras, I found myself buying a number of Sigma lenses, because Canon wasn't making what I needed. I want to say about 4 or 5. Each and every one had focusing issues. The 18-50 f/2.8 started front focusing on one end and back focusing on the other, about two years after I bought it (this was long before Canon brought out the 17-55). The 30 f/1.4 always back focused (and this was years before AFMA). I did a lot of manual guesswork with that one.

The 50-150 f/2.8 always back focused. I got into a routine where I would turn the focusing ring a little after AF was done. Worked pretty well.

Then I got a 7D and did an AFMA of +20 (!) and suddenly this became a gorgeous lens.

And then the flex board went out on it and it wouldn't AF at all. That was an expensive fix.

My 12-24 FF lens was fine, but that was probably the deep DOF and soft IQ.

Glad to see Sigma is nothing if not consistent. Never had a problem with a Tokina (love their lenses!!) or Tamron. Hell, even my cheap Phoenix macro gave me no issues, ever. But Sigma? I'm done.
Title: Re: Sigma 50mm Art 1.4 Focusing problems
Post by: thestructured on July 24, 2014, 05:20:32 PM
I got my 4th copy of the sigma art today.


Same problem, again.

Not sure whether to just hold onto it and use center focusing only until they release a firmware update or make the software to fix this in their service centers, to try a 5th copy, or to just give up.

As for 'just a few of us on the net coming here to complain'..... the few of us here have had this problem with multiple copies coming from multiple dealers. Getting one would be unlucky, getting 5 with the same problem is a manufacturing problem.


Title: Re: Sigma 50mm Art 1.4 Focusing problems
Post by: wickidwombat on July 24, 2014, 11:18:06 PM
I got my 4th copy of the sigma art today.


Same problem, again.

Not sure whether to just hold onto it and use center focusing only until they release a firmware update or make the software to fix this in their service centers, to try a 5th copy, or to just give up.

As for 'just a few of us on the net coming here to complain'..... the few of us here have had this problem with multiple copies coming from multiple dealers. Getting one would be unlucky, getting 5 with the same problem is a manufacturing problem.

have you tried calibrating it with the sigma dock?
Title: Re: Sigma 50mm Art 1.4 Focusing problems
Post by: thestructured on July 25, 2014, 01:24:48 AM


have you tried calibrating it with the sigma dock?
[/quote]

Again, as I've stated previously, along with the others having this problem, it cannot be user calibrated because it's only off center points having the issue and any calibration gets applied to all focus points, throwing the center point(s) out. Neither in camera AFMA nor the sigma dock can fix this issue, and sigma service has stated that they cannot fix it either until the sigma corporation finishes writing the software necessary to do it with (note: they said it's software to be used at the service centers, so it will still not be a user serviceable issue). At least it sounds like they are working towards making it fixable, god knows how long that will take.

Title: Re: Sigma 50mm Art 1.4 Focusing problems
Post by: mrsfotografie on July 25, 2014, 01:58:32 AM


have you tried calibrating it with the sigma dock?

Again, as I've stated previously, along with the others having this problem, it cannot be user calibrated because it's only off center points having the issue and any calibration gets applied to all focus points, throwing the center point(s) out. Neither in camera AFMA nor the sigma dock can fix this issue, and sigma service has stated that they cannot fix it either until the sigma corporation finishes writing the software necessary to do it with (note: they said it's software to be used at the service centers, so it will still not be a user serviceable issue). At least it sounds like they are working towards making it fixable, god knows how long that will take.
[/quote]

Errrhhh... so you're saying Sigma needs to calibrate the calibration dock?  :o  ;)
Title: Re: Sigma 50mm Art 1.4 Focusing problems
Post by: YuengLinger on July 25, 2014, 03:11:07 AM
So where else is this lens being discussed in English?  Sigma Rumors looks like nothing but a promo site.

B&H reviews are all 4 & 5 stars, don't see chatter about the AF problems.  Amazon has a few mentions of the AF woes, but I bet those are from CR members!

As for those here buying up to 4 copies to find a good one, consider this: If you are able to order and receive one within a week or two, you are almost certainly getting one that has been exchanged, meaning you are increasing your chances of getting another bad one.

I'm hoping Sigma comes clean and publicizes the fix(es) when and if.

I'm also hoping Canon comes up with new version of the 50 1.2 in the meantime.

I'm full of hope.
Title: Re: Sigma 50mm Art 1.4 Focusing problems
Post by: infared on September 06, 2014, 06:55:09 PM
I bought one at B&H and it front-focused and was all over the place with the focus, even with the dock I could not get it to focus In all zones..plus, I was wasting my life away doing someone eles's job! LOL.
I called B&H up, got an RMA and a return label and had them send me another copy. No problem & no cost to me.
Surprisingly this lens seems like it is right on the mark with the AF in all zones right out of the box...I am going to run it through some paces tomorrow, but I think this one is a keeper, which is great, because it is soooooooo sharp wide open!  ;D. The bokeh seems better to me than the reviews that I read,also.
Title: Re: Sigma 50mm Art 1.4 Focusing problems
Post by: LovePhotography on September 07, 2014, 12:13:12 AM
Is this also a problem with 6D bodies, or primarily 5DIII's? Thx
Title: Re: Sigma 50mm Art 1.4 Focusing problems
Post by: Eldar on September 07, 2014, 12:57:01 AM
Is this also a problem with 6D bodies, or primarily 5DIII's? Thx
I have had two copies, which have been tested on 5D, 5DII, 5DIII and 1DX. The lenses performed the same way on all bodies. The first copy was totally off and useless. The second was better, but still sufficiently unstable to be useless. I have now returned it and got my money back. I also have a 35/1.4 Art. Same problem there, with unstable AF. I bought the dock to try to help out the situation, but you cannot adjust for instability.

I do not understand how Sigma can continue to ship these lenses to customers. Their quality control is clearly insufficient and unless something radical happens and it is well documented, I have bought my last Sigma. I really wanted the 50 Art, because of the optical performance, which, when focus is right, is outstanding.
Title: Re: Sigma 50mm Art 1.4 Focusing problems
Post by: infared on September 07, 2014, 02:40:18 AM
I have a 35mm Art as well and it was great right out of the box. ..I plan on keeping both lenses as they (when working as designed) are incredible creative tools...but I have to agree, Sigma needs to do that last 10% and get a serious grip on quality control??? It is nonsense to spend $950 on a 50mm lens and then have to wonder and test and calibrate to see if your particular copy is worth keeping. 
I wonder what was the cause of the extreme difference I had between my two copies of the lens???? Perplexing to say the least.  ..I am wowed when I look at the images that the lens can create, so the whole situation is a shame for all of us.
Title: Re: Sigma 50mm Art 1.4 Focusing problems
Post by: pwp on September 07, 2014, 05:19:56 AM
I have never owned a Sigma lens with focusing problems.  But then...I've never owned a Sigma lens.  :P

I have tried a couple, and found the focus to be erratic on both. 

I think it's fair to say that some lenses have focus issues, across all brands.  The proportion of those problematic lenses does seem higher with Sigma.

I had the original Sigma 50mm f/1.4 and it was so erratic I  never built enough trust in it to actually use it on a job. Sometimes it was crazy sharp even under f/2. I had high hopes for the 50mm Art, but it looks like a no-go too.

But it's not just Sigma. My most erratic lens is the occasionally awesome 24 f/1.4II. I really wanted to love this lens, but it's in the same class as my Sigma 50 f/1.4...can't be trusted on a paying job.

-pw
Title: Re: Sigma 50mm Art 1.4 Focusing problems
Post by: switters on September 16, 2014, 02:19:03 PM

Again, as I've stated previously, along with the others having this problem, it cannot be user calibrated because it's only off center points having the issue and any calibration gets applied to all focus points, throwing the center point(s) out. Neither in camera AFMA nor the sigma dock can fix this issue, and sigma service has stated that they cannot fix it either until the sigma corporation finishes writing the software necessary to do it with (note: they said it's software to be used at the service centers, so it will still not be a user serviceable issue). At least it sounds like they are working towards making it fixable, god knows how long that will take.

Interesting. I just came to the forum to post exactly the same issue with the 35A I have. My first two copies were so far off that I had to return them; I used both FoCal and the dock to calibrate them, but they couldn't even focus properly with center point and a focus target with camera mounted on a tripod.

My third copy is much better. I was able to use the dock along with FoCal to get it consistent using center-point focus, though it did need large adjustments (something like +9, +5, +4, +3 IIRC).

However, when using outer focus points, it's ridiculously off. It will focus on an object a foot in front of what I'm actually focusing on—it's not even close. For example, I took some shots of my daughter sitting on the couch holding a friend's newborn on her lap. Even though I was focusing on my daughter's eyes (with a cross-focus point a little left and above center), the lens decided to focus on the baby's face... which was a good 8-10" in front of my daughter's eyes, and at least 12-16" below.

Like everyone else, I am blown away by the sharpness and clarity of the 35A when it hits. But being forced to use the center focus point in order to get those results is a dealbreaker. 90% of the pictures I take are of people that are moving. Focus and recompose is not an option.

So I am selling my 35A and buying a 35 IS. And as excited as I was about the 50A, I'm going to pass on that as well. Still hoping Canon will come out with a 50 IS or revamped 50/1.4. In the meantime, may just skip up to the 85/1.8 and have a 35/85 combo with two small, compact lenses. This appeals to me because my main workhorses are the 24-70 II and the 70–200 IS.
Title: Re: Sigma 50mm Art 1.4 Focusing problems
Post by: IsaacImage on October 12, 2014, 12:45:06 AM

Again, as I've stated previously, along with the others having this problem, it cannot be user calibrated because it's only off center points having the issue and any calibration gets applied to all focus points, throwing the center point(s) out. Neither in camera AFMA nor the sigma dock can fix this issue, and sigma service has stated that they cannot fix it either until the sigma corporation finishes writing the software necessary to do it with (note: they said it's software to be used at the service centers, so it will still not be a user serviceable issue). At least it sounds like they are working towards making it fixable, god knows how long that will take.

Interesting. I just came to the forum to post exactly the same issue with the 35A I have. My first two copies were so far off that I had to return them; I used both FoCal and the dock to calibrate them, but they couldn't even focus properly with center point and a focus target with camera mounted on a tripod.

My third copy is much better. I was able to use the dock along with FoCal to get it consistent using center-point focus, though it did need large adjustments (something like +9, +5, +4, +3 IIRC).

However, when using outer focus points, it's ridiculously off. It will focus on an object a foot in front of what I'm actually focusing on—it's not even close. For example, I took some shots of my daughter sitting on the couch holding a friend's newborn on her lap. Even though I was focusing on my daughter's eyes (with a cross-focus point a little left and above center), the lens decided to focus on the baby's face... which was a good 8-10" in front of my daughter's eyes, and at least 12-16" below.

Like everyone else, I am blown away by the sharpness and clarity of the 35A when it hits. But being forced to use the center focus point in order to get those results is a dealbreaker. 90% of the pictures I take are of people that are moving. Focus and recompose is not an option.

So I am selling my 35A and buying a 35 IS. And as excited as I was about the 50A, I'm going to pass on that as well. Still hoping Canon will come out with a 50 IS or revamped 50/1.4. In the meantime, may just skip up to the 85/1.8 and have a 35/85 combo with two small, compact lenses. This appeals to me because my main workhorses are the 24-70 II and the 70–200 IS.


My 35 A actually perfect ;)
Even guys at Sigma service were surprised ;)

Anyone have a success with latest  batch of 50A ?
Title: Re: Sigma 50mm Art 1.4 Focusing problems
Post by: candyman on October 12, 2014, 05:42:57 AM

Again, as I've stated previously, along with the others having this problem, it cannot be user calibrated because it's only off center points having the issue and any calibration gets applied to all focus points, throwing the center point(s) out. Neither in camera AFMA nor the sigma dock can fix this issue, and sigma service has stated that they cannot fix it either until the sigma corporation finishes writing the software necessary to do it with (note: they said it's software to be used at the service centers, so it will still not be a user serviceable issue). At least it sounds like they are working towards making it fixable, god knows how long that will take.

Interesting. I just came to the forum to post exactly the same issue with the 35A I have. My first two copies were so far off that I had to return them; I used both FoCal and the dock to calibrate them, but they couldn't even focus properly with center point and a focus target with camera mounted on a tripod.

My third copy is much better. I was able to use the dock along with FoCal to get it consistent using center-point focus, though it did need large adjustments (something like +9, +5, +4, +3 IIRC).

However, when using outer focus points, it's ridiculously off. It will focus on an object a foot in front of what I'm actually focusing on—it's not even close. For example, I took some shots of my daughter sitting on the couch holding a friend's newborn on her lap. Even though I was focusing on my daughter's eyes (with a cross-focus point a little left and above center), the lens decided to focus on the baby's face... which was a good 8-10" in front of my daughter's eyes, and at least 12-16" below.

Like everyone else, I am blown away by the sharpness and clarity of the 35A when it hits. But being forced to use the center focus point in order to get those results is a dealbreaker. 90% of the pictures I take are of people that are moving. Focus and recompose is not an option.

So I am selling my 35A and buying a 35 IS. And as excited as I was about the 50A, I'm going to pass on that as well. Still hoping Canon will come out with a 50 IS or revamped 50/1.4. In the meantime, may just skip up to the 85/1.8 and have a 35/85 combo with two small, compact lenses. This appeals to me because my main workhorses are the 24-70 II and the 70–200 IS.


My 35 A actually perfect ;)
Even guys at Sigma service were surprised ;)

Anyone have a success with latest  batch of 50A ?

I can't speak of the latest batch of the 50A but I bought mine on April 7 this year. It is my first copy. It is working outstanding on both my 6D and 5D MKIII. Straight from the box - although I checked it with AFMA. It is sharp and doesn't miss focus.
I used to own the regular sigma 50 f/1.4 and used it on my 7D. Also worked great without AF problems. Didn't like it on my FF cameras so I sold it.