http://www.bhphotovideo.com/c/product/589090-REG/Canon__EOS_Rebel_XSi_a_k_a_.html I am wanting to get this for x-mas... I have already researched the camera and those 2 lenses and I am pretty sure that's the one I want that will be useful for me... I just have one question about the XSi under the specs it says Shutter 30-1/4000 What I am really curious about is the 30 ... is it 30 seconds or minutes??? I really want to be able to take 30 minute exposure... If it is 30 seconds is there anything I can do to take longer exposures?