SIGMA 28-300MM F3.5-6.3 MACRO FOR CANON-AF CAMERAS

Rating:
Summary: Overall good lens
Review: I got this lens for about two months and tried in different lighting situations. My overall impression is that this is a vey convenient lens and saved you lots of trouble ccarrying around many lens. Two problems are obvious: barrel distortion at wide angle (under 40mm)is too serious (this I compared with Canon's 28-135mm); the squeaking sound of AF (even in one shot) is annoying. For me, this would be a transition lens.

Rating:
Summary: Very pleasantly surprised.
Review: I'd heard a lot of bad things about large "all-in-one" zooms like this. I'd also heard that Sigma was lagging behind Tamron in this type of lens. So I was doubly surprised to find that the Sigma 28-300 macro lens is not only sharp at all focal lengths, but that it is MUCH better (especially at 300mm) than a Tamron 28-300 XR LD that I compared with it side by side.

(I should point out that Tamron has a slightly improved "Di" version of the lens I tried, which has improved lens coatings and might be slightly better. But I doubt it beats the Sigma.)

This lens is even sharp wide open at 300mm (f6.3), a real pleasant surprise. This means it's not an automatic disaster if I forget to stop down, or am unable to. Of course, the edges and corners do sharpen up with the smaller aperture, but they're not bad to begin with.

There is only one thing I hate about this lens: the bokeh, i.e. appearance of out-of-focus points of light. At wide open aperture, small bright spots sometimes look like donuts with spots in the middle - rather distracting, and reminscent of a mirror lens. As you stop down, this effect goes away (which you can't do with a mirror lens) so it's not a deal-breaker, but is something to keep in mind. If you shoot a lot of photos near water near sunrise or sunset (when you're particularly prone to get reflections while using a wide open aperture)you should not buy this lens, because the bokeh will drive you nuts.

Also, the autofocus gets temperamental once in a while, which I suspect is due to the notorious Canon-Sigma incompatibility. But most of the time it's not a problem on my camera (EOS 300D digital rebel).

Despite its limitations, which for me are mostly tolerable and able to be worked around, I gave this item 5 stars because there is absolutely nothing on the market that beats its combination of price, small size, convenience, and performance.