I tried some bird photography some days ago and wasn't quite satisfied but hey low light levels, big apperture and long shutterspeeds etc.
So yesterday I did an informal nonscientific comparison between my 180mm F2,8 ais on TC 201 and 300mm f/4,5 trying to keep effective aperture and shutterspeed the same and using a sb 26 to light the subject (some logs used as feeding place for the birds)
I found that the 180 on 2X converter made way sharper images with a lot more details than the 300mm @5,6 to 11, both handheld but rested on soft but firm support (the 300 lacks its tripod collar)
Can anybody confirm this or should I retry and standardize setup even more?
I know my 180 performs really good alone and I would expect the TC201 should degrade its performance but not that the 300mm f/4,5 did that bad.