Sigma APO 170-500mm F5-6.3 DG
Sigma APO 150-500mm F5-6.3 DG OS HSM
which one is better?
how much?(about $6000)
Sigma 50-500mm F4-6.3 EX DG/HSM 有冇防震?
更新1:
+Sigma APO 120-400mm F4.5-5.6 DF OS HSM