I recently bought a Rebel XT w/ lens kit. While I'm happy with the camera, my style of photography requires a telephoto lens not just the stock lens. I was wondering if anyone had good experience with a telephoto and the Rebel XT. I'll take the camera sea kayaking and backpacking so I would like to just have a single lense for a vast majority of pictures...from flower blossoms to seals tanning on a beach. I rarely use a tripod. Would anyone have a lens recommendation? I carry the camera in a LowePro Topload AW soft case.