Originally Posted by
rpcrowe
Regarding Top Grade Lenses... There are many lower priced lenses and cameras which will perform admirably when the photographer is not using these lenses and cameras at the extreme edges of their capability. It is when you are stretching the envelope (shooting wide open and following fast moving subjects at a high ISO) that the expensive lenses and cameras come into their own.
I would suggest that birds in flight may be one of the most difficult venues in photography and one in which top-line equipment will provide the photographer a better chance of achieving great image quality.
One of the most efficient Canon camera/lens combinations, IMO, for birds in flight photography is the Canon 7D and 400mm f/5.6L lens. This combination has exceptionally fast and accurate autofocus and very decent high ISO capablity. The new 1Dx and 400mm f/5.6L lens might even be better but, the price is a great deal higher than the 7D and 400mm f/5.6L. I would consider the 7D as the best performance for price camera when shooting fast moving subjects and the fact that the 400mm f/5.6L can achieve excellent imagery when shot wide open is great plus for this lens...