I'll be traveling to Buenos Aires and Brazil for roughly 10 days. Mid way through I'll be taking a long bus ride from Buenos Aires to Rio de Janeiro. I have a canon bag however I would like to bring my gear in my backpack. Tripod Rebel XSi (450D) 18-55mm f/3.5-5.6 50mm f/1.8 75-300mm f/4-5.6 Any suggestions on what to take or not take? What about security? I suppose I'm looking for general tips/advice from anyone who's left the country to take photos. This will be my first time. Thanks.