What are you connecting it to? I don't have that one but over time I've found that I prefer to leave my CZ lenses on my RTS -- where they are a total joy to use -- rather than futz with the aperture and difficult-to-focus screens in my Canons (Elan7, 300d and 5d). It's just too much fiddling for quick operation, so if you're shooting people or other moving subjects at anything other than wide open or in very good light you might want to stick with the Canon lens anyway.

CFn4-1 -- it's a good thing