So I'm buying my first DSLR...I've done the reading, gone to the store and played with the Nikon D50 and the Canon Digtal Rebel. I've decided that I find the Canon more to my taste. So I'm going to buy that with the kit lens (I know it's crap...but for the moment, so am I!) But I also need to buy a telephoto. One of the major reasons I want to upgrade to SLR & learn more about photography is that my kids are involved in dance & theater. I want to be able to capture good close in shots of them on stage. So assuming I'm at the back of a medium sized venue...say 30ish yards away...what should I be looking at? These are older kids in fairly serious productions...so assume good "professional" theatrical lighting of the stage. I see a Tamron 75-300mm in the online kits, and I assume it's garbage. Is it? Any insight would be GREATLY appreciated.