p.3 #1 · Canon RF vs. EF lenses: Lens Size, 50mm L and 28-70mm L
howard wrote:
Isn’t it funny that the R mount has a shorter flange distance, but the rear of the lenses seem longer (deeper) than their EF counterparts?
In my simplistic view; If the focal length is measured from the end of the lens to the sensor, then the R-mount lens would have to be longer.
JP
p.3 #2 · Canon RF vs. EF lenses: Lens Size, 50mm L and 28-70mm L
EF lenses can't project backwards far or they will foul the reflex mirror. EF-S uses the same advantage but to a lesser extent (smaller mirror). The closer the rear element gets to the sensor the easier high quality optical design (at least for ultra wide-short tele range and very fast lenses) will be; and for a given aperture/quality many lenses will also be a bit lighter.
Canon has chosen to go mirrorless on it's own terms at launch, providing some compelling optics but not really aiming to maximize the potential benefits of mirrorless-smaller size and weight. I think Canon will remain mainly an EF system until they can make a a9 beater. This seems a long way off. Also it'll take a very long time to match the EF lineup's range of options. I assume there's no rush to make long Teles and T/S lenses as these should be excellent on RF mount anyway.