I largely agree with Stephen. In most respects, the 10-22 (and, I believe, several third-party equivalents as well) is so good that there really seems to be little point in buying a wide angle prime. Fantastic image quality, very low distortion, brilliant flare resistance, and very low CA as well. It's my favourite lens by quite a margin (and I also own the well-regarded 60mm EF-S macro and a pair of super-tele L-Series lenses - so favourite amongst that bunch speaks volumes, I think). Oh, and you get the instant framing flexibility of that silky-smooth zoom - just the thing for events like weddings where you may not get a second chance if you are too slow to swap lenses of zoom-by-foot.
There are two drawbacks, three maybe.
- EF-S only. You can't use it with your 1D, only the 30D. I honestly can't see this as a major problem: the 30D produces superb images at slightly higher resolution than the 1D. Speed isn't far off, only the improved focus system of the 1-Series body needs to be considered.
- Price. It's moderately expensive. (Though worth every penny.)
- The real sticking point: depth of field. At f/3.5 max, it isn't going to deliver the DOF you want. But if we are talking wide angle, then what is? Even if you had an f/1.4 prime, at the sort of focal length we are considering you are going to struggle to get a narrow DOF in any case - especially considering that the crop bodies have a larger effective DOF than a full-size 35mm unit.
Seems to me that the
right answer might be one of the primes you mention, or something similar, and a 1.0 crop body like a 5D or the 1DS. ....... At this point you stop reading because I have just priced you up into the stratosphere.....