If you bought the camera with the 18-55mm IS kit lens, then all you have to do is just to screw the UV filter on the front of the lens. There should be some threads at the front of the lens for the filter. There are different filter size for different lenses. The kit lens uses 58mm filters.
Hi,
I have a Canon EOS Rebel XSI, which came with a Canon 58 mm UV Protector. How do I install it? No instructions came with it and I've searched the web endlessly. Lots of forum talk about which type of filter is best, but nothing with respect to installing it.
Looking at it, I know it's going to be real simple - I just can't figure it out. Any help would be appreciated.
Thanks,

Chowhound
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