Mon Jun 05, 2006 1:24 pm
I used to be an advocate of lenses on adaptors... Until I started using them! Its not worth the hassle...
To get away without losing infinity focus the mount on the camera must be significantly larger than the mount on the lens, so that the lens mount and adaptor can fit inside the cameras mount. Canon is quite good for that 'cos the EF mount is big. If not, you need an optic in the adaptor to sort things out - these are usually poor quality glass.
However, you're going to lose autofocus (so no point in the big, heavy lens); unless you have a manual aperture ring, you'll have to shoot wide open - not many lenses perform well that way.
If you really want to do it, buy an M42 adaptor from ebay and get an M42 mount 300mm lens (wont cost you much) and then at least you'll be able to close the iris - on the Canon your metering will work fine in Av and Manual mode.
Or just grab yourself the Tamron 70-300mm for about £100 or the Sigma 70-300 DG APO Super Macro for £160. You won't regret it!