What are some good recommendations for a telephoto zoom lens (that goes up to 300mm) for a Canon (XTi)? Canon or third-party doesn't matter. A friend of mine asked me to recommend him a lens but I use a Pentax and my brother uses a Nikon. I do have an older Canon Rebel film SLR but never really looked into lenses, so I'm not up to date with the newer digital lenses. I know the L-series are top of the line, but I don't think he wants to spend that much money Any recommendations?