| Re: Canon 1D MKIII Autofocus- Interactive Review
Hey Drew!
Great work here. You've gone far beyond anyone else in trying to figure this thing out. I've read just about everything out there on the M3 AF issue from the 'big' sites. Still trying to form my own opinion. One thing has me puzzled and in fact, I've been wondering about this for a while. It seems that the DoF is extremely shallow, maybe just a few inches. I do realize that the closer you are to the subject, the shallower it will be. If you look at image 8049, for example, where the left pocket is in focus, none of the face is (including the side of the head) is in focus. I see the same thing in image 6202. The sleeve appears to be in line with the left ear but the ear doesn't appear to be as sharp as the sleeve. Judging from the photos it appears that there can't be more than a 5 inch distance between the pocket and the head (if that). Can the DoF be that shallow even at f2.8? Even some of the first few shots in the series where the subject is furthest away from the camera the DoF seems very shallow. I know it doesn't sound logical but could the DoF be shallower w/ the M3 compared to the M2 using the same lense? It seems like that would be easy to test.
While I don't have an M3 yet I have thought about some other ways to test. Someone mentioned (somewhere) the actual size of the FP's. I guess that can be figured out by taking an index card (or even something larger), drawing some lines on with a sharpie, lining it up with the Center FP (having the camera set up for just the center FP) and then moving it both vertically and horizontally (one direction at a time) to see when loses focus. I'd like to see a comparison of the FP size between the M2 and the M3. I'd be willing to bet that they're different with the M3's being smaller. Logic would say (at least to me) that the FP's should be just large enough so that they end where the adjacent FP begins.
Another thought that came to mind is the FPS compared to the M2's. While only 2 FPS faster, there are more shots taken within a given time frame. So where the M2 may have lost a shot trying to keep up with the subject, I think the chance of the M3 losing 2 shots (or more) in the same timeframe is greater thus reducing the 'keepers' in any given series.
Somehow I also think the focusing system is trying to be too smart. It should prevent the lense from going into hunt mode when continually focusing. I mean how far can the subject really move in anywhere from 1/5 to 1/10 of a second. The tracking seems to be ultra sensitive. Just my opinion.
Of course none of what I wrote has anything to do with the abililty of the M3 to lock focus and keep it there. That's a whole other issue.
Just my 2 cents.
Steve | 
Linear Mode
