Sigma 50mm Art 1.4 Focusing problems

[IsaacImage]

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

 

[YuengLinger]

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...

 

[YuengLinger]

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...

 

[Viggo]

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.

 

[NancyP]

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.

 

[mrsfotografie]

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).

 

[YuengLinger]

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

 

[GammyKnee]

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?

 

[sdsr]

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.)

 

[thestructured]

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.

 

[IsaacImage]

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

 

[Viggo]

...
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.

 

[fotonunta]

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.

 

[rs]

...
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.

 

[YuengLinger]

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.

 

[YuengLinger]

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!"

 

[infared]

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.

 

[candyman]

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.

 

[Loswr]

I have never owned a Sigma lens with focusing problems. But then...I've never owned a Sigma lens.

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.

 

[sdsr]

...
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...).