So I took the 5D MkIII to Loftus for some Super Rugby .....

[Phillip.Grobler]

To all you 5D MkIII users/potential users check out my review of the 5D MkIII on my site at http://www.dslrtraining.co.za/index..../reviews?id=22.

I liked the af tracking tests where can one find similar tests for other cameras?

[manus]

Hi, if you go to just my review page, http://www.dslrtraining.co.za/index....itions/reviews you will see the review of the 1D MkIV with the same tracking test, and here we compared it with the 1D MkIII.

[Phillip.Grobler]

Thanks I saw that - I m looking for similar camparesons for 7d, 60d. I was wondering if any review sites do focus speed comparisons

[manus]

No, unfortunately not, we only did it with the Pro bodies, we will obviously do it with upcoming new models as long as they are in the semi pro series.

[Grant Atkinson]

Good thread this has been, and as a photographer who tries whenever possible to photograph action, and moving subjects, faster the better (never said I succeeded ), anything I can learn to help get the most out of AF is invaluable.

I read both the two AF and image quality tests done by Manus from the links he posted with much interest, 5d3 and 1dmk4, compared to 1dmk3, and obviously he went to a tremendous amount of effort. There are many, many images to evaluate there. There was one major variable that I did not see explained though in the tests, and that was light...as the tests by Manus were done outdoors, how does one ensure that light angle, quality etc remains the same when testing different cameras? The general rating that he came to put the Mk4 a bit ahead of the Mk3, and the 5D3 ahead of the Mk4 in many aspects, if not all, which is similar to the early feedback coming in from other users of these models. Thanks to Manus for the big effort there, and for sharing with the rest of us!

PF, I think one reason that there are not too many disciplined, semi-scientific approach AF tests out there, is the huge amount of variables involved. And with pro/semi-pro bodies like the 1DsMk3, 1Dmk3, 1Dmk4, 7D the variables are infinitely greater, due to the highly configurable AF performance parameters like AF Tracking Sensitivity, AF Priority/Release Priority, there are so many options and each one can have an effect on the other....so literally tens of possible combinations of settings. It would be easier with camera bodies with simpler AF systems that do not have all the different fine-tuning settings. Plus the light as I mentioned above, if you do it outside, how do you control for the changing light when shooting at different times of day, different times of year etc. Probably really need to do the tests inside.

I have not done anything quite like that myself, but have taken thousands of images in the field of flying birds, running mammals, jumping fish etc, with a very few in focus, but enough that I keep doing it. I have used the 350D, 30D/40D/50D/60D/7D/1Dmk3/1Dmk4. Purely from my own point of view, my hit rate of properly sharp action shots went up when I switched from the 30D to the 40D, noticeably. When I started using 7D after XXD bodies, hit rate went higher, specially with birds in flight, first time I ever got approaching birds head-on sharp..then on to the Mk3 and Mk4. In certain circumstances their AF is brilliant, although as with the 7D, getting the best out of them requires fine-tuning and setting up of the AF. And I never found one AF custom setting that works for me in all situations with moving subjects, I have found that AF Sensitivity, Focus/release priority and the other AF custom functions allow me to fine-tune focus, but I have to re-evaluate between lenses..for instance the settings I like for front lit birds in flight using the 800f5.6 may not be the same as when I am using the 300f2.8 for a leopard about to descend a tree, or impala running across the grassland..lens type and max aperture has an effect, as do the physical conditions of where I am shooting. Background is critical to take into account. I have also found that it is almost impossible for me to get truly sharp action shots of very fast moving subjects in overcast weather using AF, I seem to need direct light to get really sharp shots.
Anyway, not sure how useful any of what I have written here will be, but these are my some of own experiences with AF for moving subjects (fast ones).
cheers
Grant

[manus]

Hi Grant

You are 100% correct, each subject you shoot needs a fine tuning on the AF system and even more now with the 5DMkIII, especially with the Accel/Decel setting. Regarding lighting on my test, we shot the one camera directly after the other one to minimize light fluctuations. I posted another comment on Canon 5DMK3 or 7D+5DMk2 regarding testing and results of the 5DMkIII.