Sigam 28-200mm autofocus issues
Hi. I have a Canon 20D and I also have a few EF lenses a friend lent/gave to me with an old EOS 50E. One of these lenses is the Sigma 28-200 1:3.5-5.6 DL Hyperzoom Macro Aspherical IF.
This is the lens I use on my camera the most. It's not at all wide enough, but it's got a useful zoom range and I like it. Anyway, the autofocus in it has gone a bit weird. I'm pretty sure it was like it when I was given it. This isn't the Err 99 code issue that older Sigma lenses can throw up (my friend also gave me a Sigma 100-300mm which has got that problem) but I think it's to do with the autofocus motor.
The motor makes a bit of a straining noise when autofocusing and will turn from infinity back round to 0.5m (closest focus) but it won't turn the other way and focus on anything further away than 0.5m after going to the closest focusing distance. It just makes a straining noise and doesn't move. My camera works fine with other lenses.
Does anyone have any idea what's wrong with it and if there's anything I could do (apart from use manual focus, which I have)?