Does anybody know anything about the following lenses:
1) Sigma 170-500mm f5-6.3 Aspherical RF APO Lens
2) Tamron SP AF 200-500mm f5-6.3 Di Lens
3) Tamron AF200-400mm F/5.6 LD (IF)
Are any of these out in s'pore and how much and also please advise on the quality and experiences with the lenses... Thanx!!!