Hah, finally I'm getting into birding at low cost, although not without issues -- getting the older Sigma 500 f/4.5 APO AF (not the HSM, EX or DG), I guess the one coming from the 'ZEN' times. Will only be able to easily shoot wide open, but hey, got it cheaper than a used Canon 400L 5.6 .
Does anyone with practical experiences have comments about this lens and how it compares with the later birding lenses? There are some comparisons online between the current Sigma 500 4.5 EX DG HSM and Canon 500L IS, but only Dyxxum has anything about the old one at all.
Anyways, I will post here my thoughts about it, or maybe on the lenses subforum if that is a more appropriate place. I'm just really excited about my ultra cheap fast supertele .