I used my 1Ds3 for about a month while my 1D3 was in for repair, and shot a couple weddings and a couple PGA tour events, didn't notice any AF problems like my 1D3 had. Of course my 1Ds3 was manufactured after Canon had issued the "fix" for the 1D3, so this was to be expected.
There were reports of the AF locking on to a more contrasty area even if it was noticeably far from the focus point - in one shot mode. Quite a few people said they had seen it.
I shoot fast moving dancers in low light. The 1Ds Mk III's AF works fine-even from F1.2 to F2.0. However there are, occasional, lens AF calibration issues which can be addressed with micro AF.
Beni wrote:
There were reports of the AF locking on to a more contrasty area even if it was noticeably far from the focus point - in one shot mode. Quite a few people said they had seen it.
Mine is one of those - but it only manifests under f/5.6 (or at least, is only noticable) - but I have a hunch it has to do with the difference in using cross-type AF points that engage at that point.
I have found my 1Ds2 to be better for BIF than my 1Ds3. On the other hand, my 1Ds3 is far better at everything else (mainly very low light Servo), and so for me it's a win.
I owned a 1Ds3 that was plagued with random and weird mis-focus issues at all apertures, with all my lenses and all AF points. It drove me nuts. Canon swapped it for another one that is free from the aformentioned issues. What else is there to say..? The 1Ds3 AF has its strengths and weaknesses...
