In my never ending quest for more reach, I am considering the 300mm f4, to use in conjunction with my kenko 1.4 t/c. From what I have read its IQ is very good even with the t/c.
Just wondering if anyone has one, I see Rick has, and how you find it.
I would like to use it for birds and sport, so I am a bit concerned that with the t/c, it may be too slow?