I will be getting the70-200mm f/2.8L IS and will use it on a full frame camera (5D).
I wish to get somewhere near 400mm from this to take the occasional Bird shot (a dedicated is out of the question right now), and am tossing between the 1.4x and 2x teleconverters from .
Which would be the better option:
1) 2x teleconverter giving 400mm zoom but less image quality
2) 1.4x teleconverter giving 280mm zoom with slightly better image quality and crop the image to have a field of view similar to 400mm ?