Can I ask why you stopped down to f4.5 for this? I see it quite a lot, is it purely to get the best sharpness range of the 70-200 or are there other reasons?
I normally shoot around f/4 to 5.6 to try to keep the background a little bit soft and separate the rider. It's also a question of light, I can definitely use a higher ISO, but I'd rather not if I don't need to...
That makes it a little too shallow most of the time, depends what I'm shooting. And I like to avoid the very ends of the aperture ring if possible, usually just not quite as sharp overall. If I'm far enough away though it works very well...
Really cool shot. The rider really stands out and his steeze adds to it. I would like to see this get POD, but if it doesn't its still a really, really cool shot.