Hi Im new to the DSLR scene and am a little confused with Canon lenses. I currently have a 600D and a tele lens 55-250?? I think basicallyit is a kit lens.

I want to upgrade to an L series tele and have seen a 70-200 lens I quite fancy.Its pricey but reviews are good

My question is this will that lens work with my 600D ? I dont want to buy it and find I need a pro level camera

I really just bought the camera last xmas and love it but Im concerned Im not getting the sharpness I want at the top end of the lens.

There is something niggling me about my camera not having a full frame?? what is that