Sigma 70-200 f/2.8 II APO EX DG MACRO Mini Review

Sigma 70-200mm f/2.8

I purchased the Sigma 70-200mm f/2.8 telephoto zoom lens to compliment my everyday Tamron 17-70 f/2.8. I'm generally very happy with the lens as it has a very speedy auto-focus motor (HSM is marketing-speak for "hypersonic motor", the equivalent to Nikon's "silent wave" or AF-S). This is a very sexy lens, sporting Sigma's signature black "zen finish". My friend James likens looking down the barrel to staring into the eye of a buffalo.

Kelley always looks dashing when she wakes up

It also comes with a reassuring padded carrying case. I am however a bit disappointed with its wide-open performance. Specifically, there is a noticeable loss of contrast below f/4. Since I can't afford the optically superior Nikon 80-200 AF-S or 70-200 VR lenses, and the older Nikon 80-200 AF-D lens is driven mechanically by the camera body (glacial, as I understand), I find myself up the proverbial creek. For comparison, here are two shots, one taken at f/8.0 and one at f/2.8, resized to 50%, and cropped for convenience. The original image is 4288x2848 and rather boring.

Comparison between f/8 and f/2.8

Besides depth-of-field control, reasons to use the lens at around f/2.8 obviously include moving subjects under low-light conditions, as well as low-light conditions where a tripod isn't being used. While respectably light-weight compared to serious telephoto lenses, using this lens without some sort of support is a joke - one that I must nevertheless endure. At 200mm, every movement of my body is amplified to the point that I feel like a piece of Jell-o going through withdrawal. Stopping down to a smaller aperture gives a clearer image, but necessitates a longer exposure, at which point shaking becomes an issue. This is not a deficiency of the lens in any way, of course, but I do have a lot of respect for vibration reduction or image stabilization mechanisms. This lens retails for about $1200 CDN (although I paid $900 CDN for it across the border), whereas Nikon's 70-200 VR lens costs almost a grand more. For now, respect will be the closest I'll be getting to VR. On the other hand, I have found some measure of success supporting the lens with my left-hand holding the tripod collar set to the 9 o'clock position, and since the D90's high-ISO performance exceeds that of the D300, I have some room within which to cheat. And then there's Photoshop:

Comparison between f/8 and f/2.8, after sharpening

A little sharpening goes a long way. There are some pixelation artefacts which might be ameliorated by working in RAW, and hijinks of this sort will be more noticeable in less organic circumstances, but it works, especially considering that the crop represents 5% of the original image area. In conclusion, this lens has some limitations that would be deal-breakers to people who earn their living through photography, but performs admirably otherwise.

I should clarify my comment for those that have never looked into the eye of a buffalo. It is deep and endless and contains the spirit of the earth itself. It doesn't look like an eye, as the photo of Kelley (and her eye) would suggest.  

I'm still amazed at the difference between the two f-stops. The f/2.8 looks like you smeared vaseline on the lens and it really flares around the more exposed areas of the leaves. The sharpening does quite a good job in the darker areas, but the light areas are still a little blown out. It that an artifact of information lost in the lens, or it the exposure slightly higher?