Tamron SP AF 10-24mm f/3.5-4.5 Di II LD Aspherical (IF) Reviews

I am a long-time fan of Tamron approach to lenses, so you should excuse me if I am too optimistic in my grades. When I need a pro lens for the job, I use the rental, but for my daily use my bag is populated with the Tamrons. This lens is obviously an attempt to grab the market occupied by the likes of Sigma 10-20mm and the Tokina wide-angle duo, since for a "serious" wide-angle it lacks tilt-shift capability. That said, the lens is a pretty good balance between size, weight, cost and image quality and while I only own it for about three weeks, I believe it will always stay in my gadget bag, until something much better comes around. It is actually two lenses in one, as above 14mm it covers the 35mm film frame and IMHO a solid substitute of a much more expensive 14mm prime. Below 14mm the image circle progressively shrinks and at 10mm it barely covers the crop sensor area, so between 10-14mm it is crop-sensor only. It balances nicely on Canon 20D, the zooming action is well damped and the focusing is accurate and quick enough. Manual focusing is also well-damped, but except for using it wide open and tight close-up, you would not need focusing at all, as under bright light one could stop down to F/8 or below, put the focusing at 2 m on manual and shoot away. Too bad the lens lacks the DOF scale. With regard to sharpness, the other reviews on the net complain about softness wide open, but IMHO this is not the largest problem, as stopping to just F/5 makes for a solid improvement and the lens is sharpest at 10mm, which is good news. The bigger problem IMHO is obvious purple/green fringe in the corners. At the same time,the lens has surprisingly little vignetting and barrel distortion, typical for lenses of this focal range and class.
Thus, for images made at an open aperture and at the shorter end one will have to apply quite bit of post-processing, while within 12-20mm and stopped down hardly any post-processing will be necessary.
There are, however, three caveats, which mean you may not always get the optimal results. The first is the sheer field of view and the high likelihood of getting a large luminosity range within a single frame. This is the first lens where the reportedly not the worst dynamic range of Canon 20D started to bug me. It looks like I get those unrecoverable highlights more often than I am used to. The second is that the lens occasionally misfocuses at long distances (focusing ring has only a few degrees turn from 2 m to infinity), so careless shooting without stopping down and relying only on autofocus may produce unsharp images where you least expect them. The last but not least is that you have to watch that rectilinear perspective distortion at the shorter end, when not part of your creative approach it can produce a really weird looking shot. Horizontally stretched faces may be too much to take in for some people, so one should probably stay above 17mm in people shots. Overall, a versatile lens with above average image quality and highly recommended.