I have a Canon Rebel XTi and I need help finding the best lens for taking pictures of gymnastics where you cannot use a flash. I am not a professional so I am not close which means I also need a pretty good zoom. Currently I am just using the 55-200mm f1:4.5-5.6 lens which zooms well but does not take good low light pictures. I am just taking pictures of my daughter but would really like to be able to get good pictures. I need to keep the price reasonable too since this is just recreational photography. Thanks for any help you can offer.