Just getting into photography, and got a Canon EOS 400D with standard 18-55mm lens. Now want to add a second lens so when I take children to the zoo I can actually get a close up of the animals, or when I go motor racing I can get a close up of the action etc. I'm no professional, just a family man who wants to take good photos on family days out, holiday, sports events etc. I've read that a 55-200 mm lens is a good second lens, but having read some threads it seems 70-200 or 300 is best. Any ideas please would be gratefully received.