We’re also told that a new USM motor will also be introduced some time this year, and it will be called “C-USM”, which stands for Compact Ultrasonic Motor. This technology is likely to first appear in a new 50mm lens.
No no no no no!!! It is a compact USM motor that made the last 50mm f1.4 a piece of unreliable garbage. Why would you do this again when you already have a reliable usm motor that is small enough to fit in the new 24, 28, 35 mm IS lenses?
So many people still carry the 50 F/1.4 because the F/1.2L is (for various reasons) not for them. These folks are clamoring for a new 50 with a modern/fast/accurate AF system. Or, put another way: many people still use the 50 F/1.4 with it's 20+ year old clunky-not-quite-ring-USM as the best AF 50mm lens for their needs.
Canon designers: needs don't get more unmet than this.
Please don't shoot for the stars with new tech on a bread and butter lens; save that for a new 180L macro or a cool new pancake lens. But for 50mm, give us what we know
you can -- an impeccably well put together "IS refresh" in the 50mm focal length -- so many of your users will be happy if you did.
And please no STM here -- I want minimum time-to-target, not a smooth focusing lens for video.
If they pooch the USM on the new 50 IS, they'd be handing this focal length to Sigma.