Sigma 35 Art

[Darren Irwin]

Hi everyone. Is anyone else have serious AF difficulties with the Sigma 35 Art? I've tried calibrating it and microadjusting it and it's just incredibly unreliable. I was willing to blame myself initially but have been testing it in the studio on a tripod and it misses 40% of the time. The weird thing is, it used to work brilliantly.

 

[zombiesniper]

I don't have this lens but if it used to work well, can you remember any difference between then and now? A drop, new camera body, temperature, moisture etc. If it work well at one point it would lead me toward troubleshooting a user error first and if no user error presents itself then possible lens repair may be required.

 

[Banjor]

I have been disappointed with the focusing accuracy of the 35mm Art in indoor light. It seems to focus quickly, but misses the mark, even when spot focusing. It’s bang on in sufficient light, especially after calibration.

Were you shouting in different light when it was working before?

 

[ac12]

Same camera, same focus mode and focusing point?

Same focus direction; infinity to focus or closest to focus?

Has your studio lighting or the target/subject changed?
As Banjor noted, darker and less contrast makes for less accurate or more difficult focusing.

 

[jcdeboever]

I have had issues with various Sigma lenses, not that one. I would never buy one again. Most were way off and when you tried to correct it to hit the mark, it would then back focus or front focus. It drove me near insane. I ended up switching systems and now I don't have any of that. Last year, I helped a lady at a botanical garden with the 85 art. It did the same thing as mine did. I proved it to her on a flower, it was focusing way to the left. I moved the focus square to where I thought it might focus at, bingo. She didn't have it long and was able to send it back and she picked up the Nikon 85 1.8 or the micro, can't recall, and was very happy.

 

[Destin]

I’ve never used that lens. My 135 1.8 is often off by a touch, but I’m also shooting at razor thin DOFs so it could well be user error.

One option is to send your camera and lens into sigma to have them calibrate it.

But I’m honestly tired of calibrating focus on all my lenses constantly. This is one of the biggest reasons I’m considering switching to a mirrorless setup completely.