Sigma 400mm f/5.6 APO Tele Macro
Data from various other sources, comments from Rusty Dodson
Get close-up shots even when you're physically distant. These macro capabilities add an entirely new dimension to photographing flora and fauna. With a minimum shooting distance of 63 inches the lens achieves a 1:3 reproduction ratio. Two SLD glass elements to help deliver outstanding optical performance. And the lens length never changes, thanks to an inner focusing mechanism.
I've owned 3 versions of this lens, the very economical and decent for the money 400mm f5.6, the APO 400mm f5.6 and the telemacro version. Each one got consistently better. I'll do a quick run down of all 3 instead of an entire page for each one.
The Sigma 400mm f5.6 was a dirt cheap and decent lens. I actually bought it on accident while I meant to purchase the APO version. I still used the non-APO version for several months. The lens was actually quite well made, and light for a 400mm prime lens. The images were decent and very good at f8. The lens sold easily.
The second version was the APO version of the Sigma 400mm f5.6. This lens is a very economical option, it's reasonably sharp and nice with colors. Again by f8 it's as good as any lens out there. This lens also sold without any problems.
Finally, I purchased the Sigma f5.6 APO Tele Macro lens. Optically I can't say for sure that it's that much better than the non-macro version, but it is more versatile. This is a 400mm lens that will focus close enough for insects. The close focus ability gives one a lot of the convenience of a zoom but with the quality of a prime. This is largest and heaviest of the 3, but also the most versatile. I can't say it's razor sharp at f5.6, but it is sharper than the price would suggest. I have published images shot with this lens wide open. If you get the chance grab the HSM version. The lens I owned was the standard AF lens, and it was slow. This lens also sold well and made me money.