Hi, I have a number of cokin 'A' filters (bought cheap) to try with my Rebel. I understand that you can purchase an adaptor to use 'A' type filters with a 'P' type holder. Can you please explain the merits of doing this. I no you can play around with your photo's in programs like PSP etc. but I want to try getting the picture at the time I press the button that's why I bought the filters ( just in case someone was wondering why I should use filters with a digital camera).