I went ahead and purchased this lens online last week and got it yesterday. I noticed immediately that my copy front focuses badly. I dialed in a +15 and it seems to be fine. However at longer distances it misses focus. Is this normal? I plan to use this lens mostly for portraits, but it would be nice to use it at 15+ feet at weddings with very low light. Should I send it back and get another?
I'd say yes, if you have the patience. When this lens is focused right it's a stunner. Mine was working really well until I started doing close up shooting and near MFD it front focused a bit, so off to Sigma it went... will see if it's better when it comes back.
There are lots of threads on this issue in the Alternative board.
The short answer is yes, the problem is very common. Check the threads there
to get a sense of how likely you are to solve it with another copy of the lens.
It's a lens that presents me some frustrations, but I treat it like a pseudo-auto-focus
lens. I check the focus by tweaking it manually and by focus bracketing. The resulting
images are generally _very_ nice. I work around its limitations.
I had exactly the same issue. The front focus was really bad and it needed +15 MA. Plus, the bokeh behind the focus point was terrible. It was like a lot of bubbles with heavy CA. The only nice thing I had to say about this lens was the bokeh beyond the focus point.
I immediately returned mine. Didn't bother with replacement. Someone suggest going to a local store where you can try different samples and pick the best one. I think I will follow this advice.
Personally I think they are all like this.
I gave up after three.
The three lenses I tried were different ages and from different countries, so I doubt I got just a bad batch.
Some are just worse than others.
Some users shoot in similar subject distance ranges a lot (e.g. all portraits or all landscapes) and don't notice it maybe.
Some users aren't critical enough to notice it maybe.
I'd love to be proved wrong, as if this lens could autofocus properly I'd own it in a heartbeat as I like the look it gives.
I was considering the Sigma 1.4 50mm over the Canon, but just about every review praises the lens when it works right. Reviewers talk about it being sharper and 1.4-2.8 than the Canon, but that it is difficult to get a good copy. I'm willing to loose a little sharpness wide open and will be getting the Canon lens to avoid having to hassle the problems that seem to occur with Sigma. Shane, thanks for bringing the problem up and convincing me to go with the Canon.
