# Sigma art focus issues : still a problem ?



## edurieux (Jul 26, 2015)

Hello folks,

I am thinking about acquiring the 50 Art from Siga but I'm a bit scared with the focus issues. Is it still an issue on today's lenses ? Would you purchase the USB dock with it ?


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## candyman (Jul 26, 2015)

edurieux said:


> Hello folks,
> 
> I am thinking about acquiring the 50 Art from Siga but I'm a bit scared with the focus issues. Is it still an issue on today's lenses ? Would you purchase the USB dock with it ?



I would buy the sigma dock because it allows you to apply firmware updates for the lens. So, if canon releases a new camera, the lens can be updated with a firmware update to make it work with this new camera. 
Of course the dock will also help you to apply AFMA.

I bought my lens last year in spring. I do not have focus issues. I can't tell you if new production models are free of issues. You have to try.


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## YuengLinger (Jul 26, 2015)

Afaik, Sigma has not issued a firmware update for the 50A as yet.

I have the 35mm A, no problem, but tried one 50A and gave up.

Personally, having a 5DIII, which can AFMA, I see no point buying the dock with the lens. You could try the lens, see if it works, then decide.

Good luck!


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## Mt Spokane Photography (Jul 26, 2015)

Yes, it always will be a issue with 3rd party lenses and Canon DSLR's (Unless using Contrast Detect). The simple reason is that a 3rd party lens tells the camera that it is a Canon lens by sending a lens code.

This means that the camera makes internal adjustments to match the Canon lens, ans to determine how many focus points are allowed, as well as other optimizations.

This causes a lot of issues, and can be different for different cameras. Using the dock adjusts front / rear focus for just one Canon camera, its certainly worth getting, but AF issues keep cropping up.

Its not the fault of 3rd party lens makers, they do a amazing job with what they have to work with.


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## edurieux (Jul 26, 2015)

Thanks for your feedback. I will pick one during the week and see later is the dock is needed !


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## mystikjoe (Aug 4, 2015)

I had a sigma art 150-600 lens that was what I think a decentered lens. that's what sigma told me the replacement was flawless. the original lens wouldn't focus past 280mm and I couldn't correct with dock. food for thought maybe just request a replacement.


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## sdsr (Aug 4, 2015)

Do any of you Sigma 50mm Art users have much/any experience focusing this lens manually? I have a slight interest in using one that way on a mirrorless camera (it's one way to avoid the AF problem, but I tend to prefer MF anyway), and while it surely won't be as good for MF as a lens that was designed to be MF only, I'm hoping that it would be considerably better in that regard than the Canon 50mm 1.4 (or at least my copy of it - its focus ring is not well damped, making the process rather fiddly).


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## Viggo (Aug 4, 2015)

I'm in my third 50 Art and 5th Art lens overall. This current 50 is the only one without the inconsistent focus, and it's bought most recently. I bought the docking, but what I have learned is that when you get a working Art lens, the docking is absolutely not needed. My current 50 missed by the same at EVERY distance , so I set the afma in camera. And that was what other said when I had my problems, "I have a working copy, no afma or docking needed".

If it's not the same afma value at every distance you will never get it to work. 

Buy the docking only if a new firmware comes out, if you're buying the 50, no need.


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