Alex:


"I'm primarily into landscapes, so this lens is *probably* a good choice. "


Maybe, but maybe not. Have you used a lens this wide? Landscapes can look terrible, with lots and lots of sky and foreground. Sometimes, that works; often, it doesn't. If you want a wide photo without the huge sky and foreground, try using a medium focal-length lens and doing panoramas. Canon's "stitching" software makes this relatively easy. (For best results, you should use a panning head and ensure that the lens+camera rotate around their optical center, but you can do pretty well with a ballhead with a panning base, as long as you are carful that both the tripod plate and the camera are level.)


Here's what I mean. I deliberately shot this to demonstrate what a super-wide angle photo can look like. This was taken at 10mm.








What I've found the most fun with the 10-20mm is getting "up close and personal" with objects. Here are two examples. The first is of a shrivled-up apple in a field, also at 10mm. I was lying down, with the lens only inches from the apple.








The second is of some oats. (The field is near the stable where my horses live. Seeds get dispersed through the horses' manure and by birds.)








Remember that perspective has NOTHING to do with the lens focal length. It depends entirely upon the relative position of the camera and the subjects. However, with a super-wide-angle lens, one can get closer to an object for the same size on the image than with a longer lens. The perspective distortion can be fun, especially with rounded objects like the apple or a deep object like the oats, giving more appearance of depth.