I've been shooting for a few years now, and am finally deciding to get serious about it. I am upgrading to a 50D soon, and would like to get out of the 18-55 kit lens and into something better. I am mainly doing portrait work and landscapes right now... but I am wanting to get into photographing local concerts, and may be brought on as a 2nd shooter for weddings later this year.
I know that I want a zoom lens, with at least a constant 2.8 aperture, and would also like to see something with a high speed motor. I've been researching various lenses for a while now, and thought I had my choices down to either the Canon 17-55 2.8 IS USM, or the Sigma 24-70 2.8 USM. The more reading I do though, I'm starting to think I may not understand the effects of the 1.6 crop factor as well as I thought. My first question then is what would the Sigma's wide end be on my crop body? I've calculated it out to be about 38mm, but would like some verification. If that is indeed correct, I think I'll lose too much on the wide end to go with the 24-70. Most of my portrait work is done in pretty cramped spaces...
If someone could help me figure this out, it would be much appreciated... I'd hate to drop that much $ and then find out I don't have enough wide angle for what I'm shooting... Also, If there are any other suggestions for different lenses, I'm listening. My budget for a lens is going to be around $1000. Thanks in advance.
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