Although some reviewers mention focus issues, I haven't seen any mention of the auto focus failing after time, like the Canon 1.4. Is this true?
49855
Have had my Sigma 50 for a year (w/a Nikon mount) and to date it has not failed yet. There are times when I prefer manual, but the AF hasn't failed.
49856
I haven't experiences it or heard anything about complete failure. The issue has always been a high rate of focus failure or chronic front/back focus for some copies on some camera bodies. Personally, it's never happened to me. When you're shooting at a very wide aperture, pushed in pretty close, your depth of field is so shallow there will often be some errors. I just accept that and do a lot of refocus and reshoot to cover myself, but I'd do that with any lens under those conditions.
49857
I've had mine for two years and it hasn't failed. Never heard anyone mention the AF failing. AF back focusing, or front focus, yes. But depending on what Canon body you're using most the time Micoadjustment enables you to tweak the lens to focus properly.
845656
I wonder if you are using the camera correctly. If you set the camera to continuously focus, and then try to do focus-and-recompose, you will get out-of-focus photos most of the time. The Tamron all-in-one lens, like any all-in-one lens, is not the best lens in the world. But it isn't horribly bad, either. And it normally will not do a lot of focus hunting in decent light. If you are new to SLRs, you might begin by making sure that you aren't the problem. FWIW
35284
For some reason, Canon seems to use FULL TIME Continuous AF - which is active even when you're not touching anything - and turned it on by default. Very annoying feature. I didn't realize this either until I popped on a noisy EF lens and it just wouldn't stop auto-focusing. I suspect Canon decided this would somehow make the camera "easier to use".
250583
No, it would be great if it had that option though. I haven't had any issues with the auto focus because the camera itself can easily be moved around.
1974696
Yes I too bought this lens not too long ago (under a year) noticed the sound immediately however I expected that heading it from many sources, what troubles me though is that it's been only 6 months and I've had to send it in for service because my auto focus motor failed.
512484
This is not an official statement but I've been shooting a lot. And I 99% use single point AF, manually setting focus point according to my subject. I never noticed a left focus or lock up problem.
220774
I have the same problem with the autofocus for video recording (even when set to "Full AF"). It occurs mostly during zooming in and not as much when zooming out. Sometimes, after zooming in, it will lose the focus and then regain it or not at all at times. This problem has occurred in bright light and sun outdoors and indoors in decent and dim light.It's too bad since the quality (color and clarity) seems excellent.
100425
No, only when you want to focus, then that is normal. The there is a delay before the next shot but one can skip that if you want. Best camera we've had, great close-up shots.
117908
The autofocus is a little noisy, if that's what you mean by 'lens mechanism'. No other issues that I can think of.
1209309
As of the August 2014 update it has autofocus. Not even the tech support guy we spoke to knew that. The autofocus works fine. Not as fast as a canon dslr, but good enough.
229479
I have had one for about a year. I use it on Autofocus and hand held.I have been pleased with the quality of pictures I have gotten.RZ
1409502
Yes, I must wait for about a second or two for the camera to reach focus. This is in the program [P] mode, or the Auto. Also, if I see a perfect picture, there is a noticeable time lapse between when I press the button and the shutter "releases" [electronically]. This means that on many occasions I have to take another picture and hope for better.
229628
No, autofocus doesn't work. You have to set the camera to manual mode and manually focus. However, it's not that difficult once you activate the zooming mode to help you focus.
172428
hi george, in my eos canon 350d, work very good, but only in manual, not in autofocus
1321063
AutoFocus was fine. Some circumstances, e.g., bird watching, require manual focus.
447638
I had heard about the focus problems but we have had no problems with it what so ever. At wide open apertures, the depth of field is extremely tight, so I am guessing that some people who have less photographic experience were the ones complaining, because even at those apertures we are producing tack sharp images, on auto-focus or in manual on our Canon cameras, a T5i and a 60D. Sigma has released an updated version of the 50mm in their new "Art" lineup, so if you still have concerns, save up for that one. I've played with it at our local camera store and it is beautiful!
1209305
No auto focus control, even if you're using lenses with AF. (At least for the canon lens mount, though I expect all the mounts are like this). Also, iris/exposure control is limited on some lenses. Check their website to see what works.