A couple years ago I found myself shooting more and more sports and my 5D classic was not cutting it as much as I would like. I picked up a used 1D Mark III that had had the sub-mirror fix. I didn't try a bunch of fancy testing, I just used the camera.
For over a year I shot volleyball, basketball, soccer and softball and the 1D3 just churned out sharp results. The camera was also a revelation with my fast primes in low light, just nailing focus with no fuss.
So this winter I got an unexpected bonus and sprung for a 1D Mark IV and sold the 1D Mark III with some reservation. I hate letting go of equipment that I know works well.
I think my nervousness made me do it, but I decided to try some focus testing with the 1D4. I had my kids run towards me while shooting bursts. Soon I had a real Rob Galbraith moment. Most shots were in focus, but some were inexplicably soft. Oh no! I'd sold my trusty 1D3 for this?
Concerned, I went ahead and just started using the camera. I shot mens gymnastics. Then I shot softball, lacrosse and soccer. And in the end the 1D4 focus is just like the 1D3 - it just nails focus in real world use.
You would think the unpredictable motion and constant shifting of subjects of real world sports would be the toughest thing to shoot, but the 1D III and 1D IV seem to just excel at this. My conclusion seems to be that coming up with a reliable AF test is harder than one would think. In some respects all you can do it put the camera to use. And getting the custom functions right for the type of sport is probably half the battle.
