Sigma 50mm Art 1.4 Focusing problems

[e-d0uble]

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.

 

[IsaacImage]

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

 

[Eldar]

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.

 

[IsaacImage]

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

 

[GMCPhotographics]

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?

 

[YuengLinger]

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.

 

[GMCPhotographics]

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.

 

[Eldar]

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

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.

 

[wickidwombat]

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...

 

[YuengLinger]

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.

 

[playaz]

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?

 

[Viggo]

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.

 

[playaz]

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?

 

[Mika]

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.

 

[Eldar]

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.

 

[Mika]

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!

 

[GMCPhotographics]

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....

 

[mrsfotografie]

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.

 

[Mika]

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...

 

[Viggo]

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