All Novotron Lens adaptor rings retain the lens ability to focus on infinity. They do not transmit any functions between the body and the lens.
Most cameras provide the ability to do "stopped down metering" with the diaphragm stopped down or allow an aperture priority automatic exposure, so the Lens adaptor ring will allow you to end up with a correctly exposed shot with the use of lenses from other manufacturers on various cameras.
With Leica-R-lenses, having a wide stand back protection of the rear lens, (lenses 2,8/15mm, 2,8/19mm, 2,8/24mm, 1,4/35mm and Zoom 3,5-4/21-35mm) there will occur a malfunction of the Canon EOS, the mirror will get caught on. These lenses cannot be used with the adapter and the Canon EOS