Hi:
I apologize for the delay in responding here with photos but I have been learning to use my camera and experimenting.
The attached shots 7624-28 (in the next post) and the af points picture show my results with the Tamron 100-400. The subject (one of my primary subject types) is my son's crew shell mid-race.
Shots 2267, 2272, and 2281 show in each case the first shot of a burst taken with the Canon EF 100-400 f/4.5-5.6L is II USM. The photos look well focused IMO and the other members of the bursts look similar to me.
With my untrained eye I see clearer focusing in the pictures with the Canon lens when taking pictures at a greater distance and moving faster. The only mitigating circumstance I can think of here is that the AF points for the rowing pictures are not fully occupied by the rowers, however, what is inside the focus point is not great anyway. The Canon lens has been out a while now but I'm thinking about saving up for a used one anyway- it seems to produce a nice result with this body and would be useful for many years based on what I expect to have as subjects. It's a lot more money but I only get one chance to record my sons growing up.
