Mon 18-Feb-13 10:33 AM | edited Mon 18-Feb-13 10:35 AM by olivierrychner
Coming back to the subject of Sigma's comparable products, you have to be prudent and to distinguish between three lenses: first, there's the 50-500 "Bigma", the latter incarnation of which has HSM and OS, and which has never had an equivalent in any manufacturer's range.
Then there are the 120-400 and the 150-500. When they appeared some years ago, the "Frenchies" at Chasseur d'Images reviewed them in the same article, and concluded that the 120-400 was better value, most notably because the 150-500 is basically the same lens with one more glass element acting as a TC, resulting in a f/6.3 lens whereas the "shorter" 120-400 is f/5.6 at the longest end, resulting in better AF operations.
So it makes three comparable Sigma lenses that one could envision as alternatives to the venerable Nikon 80-400VR (and to the old Sigma 80-400 OS, which some thought better than the Nikon!). As I have written above, I'd go for the 120-400 if I were to buy now, for the reason that I think the Bigma is too heavy and I am wary of the f/6.3 of the longest end of the 150-500. And also because I think I have better ways of covering the wide-to-120 "gap" of the 120-400!
Have a great day!
Olivier Rychner __________________________________________ Jetez un oeil à ma galerie if you feel like it! And it's a bit void as of now, but I also have a Nikonians blog
Auta i lomë! And my Nikon's only awaiting daylight...