I wouldn't bet on that. AES and the various public/private key algorithms are well within reach of embedded, low power processors transmitting small amounts of data (i.e. camera/lens protocol). If Canon RF lenses communicate via a high level, serialized channel over the new pins the packets could use strong encryption.
If Canon doesn't etch those keys into the silicon itself, with no read out capability, then they can and will be discovered. But understand hiding the keys on the silicon is not a new thing (Apple's Secure Enclave). So it is possible the RF protocol is out of reach of 3rd party lens makers. I hope Canon is not that short sighted and greedy. But it is a possibility.
I probably missed some earlier posts in regard to this discussion, but isn't the mount distance a problem going RF to EF? Any such adapter would have to include glass to compensate for the back of the lens being so far from the sensor. Doing the glass right so you maintain 90-95% of the original lens IQ would put the price close to the cheaper RF bodies (by the time they appear).
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Flange distance is definitely a problem! I think it's 44m for the EF (full frame) and EF-S (APS-C) mount and the RF is 20 mm, the EF-M (M5) is 18mm
so a diopter would be needed in the adapter itself.
HOWEVER! The KEY issue is using Glass versus High Refractive Index Acrylic (i.e. plastic lens) which will make it VIABLE for Canon, Wooden Camera, etc to offer an RF to EF mount converter WITH the built-in Neutral Density Filter slot-based or dial-in setup AND with focus and iris ring controls at an acceptable price point!
Using High Refractive Index Acrylic plastic allows a manufacturer to PRESS MOLD the diopter shape and then to use fully automated buffing to get the surface clarity needed for such a RF-to-EF converter at only $275 US (230 Euros) to $350 US (280 Euros) for the entire adapter! Doing the diopter piece out of glass would bring the price to more than $1000 US (750 Euros)!
Plastic lenses are so much clearer nowadays, and if they are coated with thin-film, optically-clear ceramics to toughen the surface of the lens against scratches and glare, then it would be quite easy to make such assembly very cost effective enough that consumers would be made very happy with such a high quality lens adapter at that magical $350 maximum price point!
So for Canon and Wooden Camera, I would DEFINITELY take a look at High Refractive Index Acrylic plastic for any diopter elements and PLEASE do add a drop-in or dial-based neutral density filter system AND proper iris and focus rings with easy-to-see, glow-in-the-dark markings and numbers!
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