5Diii and sigma 85mm 1.4 slow focus (maybe)

[thatcherk1]

I may just be paranoid, but I have a sigma 85mm 1.4 and love it so much. I just got my 5Diii and it seems like the motor is moving slower than it did on my 5Dii. It still gets focus, it's just the motor takes longer to get where it needs to go than I remember on my 5Dii. I don't have my mark ii with me right now so I can't do a side-by-side comparison.

Does anyone else have this lens-camera combination and noticed the USM motor moving slower on the 5Diii than on the 5Dii.

I've not noticed anything odd on my canon lenses. And I don't know if I'm just paranoid and I'll pop this thing on my 5Dii and it will react the same.

 

[Mt Spokane Photography]

Its certainly possible. Sigma reverse engineers the Canon Autofocus process, and has repeatedly had lens with issues over the years. As I recall, they had a fix for the D30 and D60, then it broke again when the D10 came out. Since then, they seem to work.

There is no guarantee that any Sigma lens will autofocus properly when a new Canon body comes out. I had 4 Sigma EOS compatible lenses that would not work on Canon DSLR's. Either they would not change the aperture, or would not autofocus.

Sigma charged me $100 to fix my 105mm Macro with a updated chip, but the other three were out of production, so they were useless on a DSLR, they would not change the aperture, so manual focus was not a solution.

I sincerely hope thats not the issue for you. Just the same, I will not buy Sigma any more, even though I approve of having competition.

 

[thatcherk1]

Yeah it's a bummer. I bought the sigma because most reviews I read suggested that as long as there were no focus issues, the image quality at 1.4 beats the canon at 1.4. I didn't even buy it as the "cheap" option. I might be regretting the decision now. Don't know though.

Hopefully I'll be able to test it side by side with my 5Dii later.

 

[jbenhartley]

This is very interesting to me!

I just purchased the Mark III and am moments away from getting the Sigma 1.4
Again, not because of cost issues, but rather it honestly seems like a better lens in a number of ways.
I know not in build, but in focus speed for sure.

Keep us posted please, I would greatly appreciate it. What Mt Spokane Photography said makes a lot of sense about reverse engineering and its downfalls for new gear.

Im really curious about that.

 

[Jimlevitt]

My 5D3 arrived on Friday. A second-hand Sigma 85/1.4 came earlier in the week. I used the pair together this afternoon, at f/1.4 the whole time. I'm happy so far: I think I'm getting better results from the Sigma wide open than I can from my Canon 85/1.8 at f/2. Haven't had any time to microadjust it, either.

I can't say anything about the focus speed. I tested the Sigma on my 5D2 around the house the day the lens arrived. Nothing seemed amiss on the 5D3.