Thanks Ron, but the K-5 isn't really fast enough for discus this close. Catching the discus as it left his hand was a matter of luck. This is a young boy. An adult would be spinning considerably faster.
Look at these two consecutive shots from earlier in the session (the 2nd I've left uncropped):
The discus is already out of frame. This is with AF-C. With a semi-static sequence like this, (the thrower moves 2 steps forward as they twirl), I may have been better using AF.S for the extra fps. (Not sure how sharp it would be though).
Also I decided after this that it was a waste of frame space to laterally centre the thrower, and changed from Centre-Point Focus to Selected Focus Point (bottom-right point, as used in the 6-shot sequence I posted). I was operating hand-held, but wasn't moving the camera too much.
Dan.
Last edited by dosdan; 02-12-2013 at 06:06 AM.