Playing the Sigma Game

Sooo...I bought a Sigma 50 1.4 from B&H and initially thought it was a good copy. I took a couple of shots outside and thought it looked like it was front focusing, so I some test shots.

Unfortunately it is front focusing pretty bad...so much that I can't fix it with MA. Just to be sure I'm attaching 3 samples of 100% crops..

So, the question now is do I send the lens and camera in to Sigma for calibration, or do I send it back to B&H and ask for another lens? I would like to hear from people who have been through this and recommendations from them. I'm not interested in hearing how people will never buy Sigma again...just want to figure out the best way to resolve this!

First is 0 MA, then +20 MA

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-20 MA:

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If you send it back to B&H you will be playing the sigma game all over.
If you send it to sigma with your body then you'll get 100% perfect focus and centering at all distances.

If it's new from B&H, then return it or exchange it and try your luck with another copy. Or send it into Sigma directly under warranty - it's obviously not up to standards.

I sent mine directly to sigma....quick service, no issues.

Personally, I would go with having B&H swap it out. If the next one does the same thing, send it in for calibration.

I met a pro landscape photog last fall and he told me that every time he gets a new body he sends the body and all his lenses to Canon for calibration. I thought that was extreme but he made the point that he never has any issues that way.

Does anyone know how long that takes? How long they will have your gear during this process?

jcpoulin wrote in post #12436811
I sent mine directly to sigma....quick service, no issues.

Did you send the camera as well?

DonSantos wrote in post #12436798
If you send it back to B&H you will be playing the sigma game all over.
If you send it to sigma with your body then you'll get 100% perfect focus and centering at all distances.

Not neccessarily! I bought the Sigma 50 1.4 a couple of months ago from Abes of Maine and it was a terrible copy. I asked Sigma what I should do; send it to them or back to Abes? They suggested I send them the lens along with my camera so, I sent it to Sigma along with my 5DmII. I just got my camera and lenses back a couple of weeks ago but only recently found the time to check them over. The 50mm is only slightly better but that isn't saying much because it is shifting focus so bad that I cannot even ma it. Using a Lens Align Pro I can take 5 images all of which focus at different points and the focus is incredibly soft. Even at f2.8 the focus is soft. I have ma'd all my other prime lenses with great success but this Sigma 50 has me pulling out my hair because it is so erratic.

I have been on the phone the past two days with Sigma and they are picking the lens up hopefully tomorrow. I know if they do not fix it this time I will ask for either a new copy or a complete refund because it is definitely a lemon.

So lets say I send my camera+lens to Sigma and they do their adjustments. Do they adjust the MA or something within the lens?

I am happy with my copy, but I guess it could improve a little; I am just worried that by sending it to Sigma for adjustments will cause the lens to work well with one of my camera while its terrible on the other one.

Just send it to Sigma without your body. Send it along with a CD with your test shots. Should get it back within 10-14 days but well worth it.

It makes no sense, how can sigma be that bad at a out of box calibration? I mean if canon can do it right how sigma not???

mikeassk wrote in post #12438251
It makes no sense, how can sigma be that bad at a out of box calibration? I mean if canon can do it right how sigma not???

canon doesn't always have perfect results, either.

I've been in your exact situation. I sent it to C.R.I.S. in AZ, but even when I got it back, it wasn't quite all that great. It wasn't bad, but in the end, I sold it. I would send it back and hope for a better copy. Oh, I also sent it without my camera. What I should have done was just send in the camera as well so they can make sure it works perfect. They might have other bodies they test with and calibrate it to that body and not yours. Just my 2 cents.

csshih wrote in post #12438286
canon doesn't always have perfect results, either.

50mm seems like the easiest lens to make... whats the deal

csshih wrote in post #12438286
canon doesn't always have perfect results, either.

Indeed. I had to return my Canon 50mm f1.8 under warranty as it was front focusing very badly. They ended up replacing it instead of repairing it which I was surprised about.