Hello folks. First post here. Hopefully you guys can solve my issue (or guide me towards a solution).
I've got the above mentioned lens for sale and a couple of days ago someone passed by to test it (and maybe buy it). Eventually she didn't buy it (for now), because she pointed out a rather strange phenomenon. Something that has never really occurred to me in the 3.5 years that I've used this lens.
When you focus on a subject the IS obviously kicks in. Apparently with this lens, the IS can generate quite some noise, but that seems to be quite 'normal'.http://www.canonrumors.com/forum/index.php?topic=413.0https://www.flickr.com/groups/canon_...7619031700221/http://photography-on-the.net/forum/...d.php?t=807930
The thing that worries her (and myself as well now) more is that the AF seems to hunt a bit (somewhat as described here: http://www.dpreview.com/forums/thread/2975199
). We took a bunch of pictures (in good light conditions) and almost always you can clearly see on the distance scale on the lens that it has to hunt a little bit. It looks like it focuses a tad too far and then jumps back, all very quickly. This generates a (small) shock effect.
There is no difference if all focus points are activated or just the center one. We only tested it with her camera (450D). Mine is already sold so I can't test it myself anymore.
. I believe that the camera was set up in "One Shot" mode (no AI Servo).
We tested other lenses (EF-S 10-22, EF 70-300)as well to rule out a possible camera problem. They didn't have this issue.
Focussing itself goes quickly and never fails. The contact points of the lens are clean.
I was wondering if this kind of behavior is normal? Are there any tests that we can do to check if there's something wrong with the AF (or even IS)? Again, the lens always focuses correctly, but it seems to hunt a bit.
The lens is obviously out of warranty and I don't want to sell someone a pig in a poke. If there's really something wrong with it, I'd rather not sell it.