ColD wrote:
I like the look and idea of the 15-85mm. I could stretch the budget to get there, but do you think the 15mm is wide enough for architecture shots, church steeples, bridges, landscapes and the like? Otherwise I have been looking at the 10-22mm wide angle to suppliment my standard 18-55mm.
It
could be. Like I said before, it's a compromise but not a replacement for what most would consider to be a true wide-angle lens on a crop-frame body such as the 10-22mm. The 15mm wide angle is the equivalent to the 24mm full-frame focal length, which is a traditional focal length.
The Canon 10-22mm would be a great choice for architecture. Tokina has an 11-16mm f/2.8, which is pin sharp but it is very pricey.
ColD wrote:
Although changing lenses while on the move sounds like it could be inconvenient.
Your mileage may vary. If you have a suitable bag, I don't think it's much of a hassle but some would regardless.
Unfortunately, convenience (in the context of having a wide focal range, i.e. not having to change lenses) and image quality are usually mutually exclusive.