RF-S Lenses on Full Frame EOS R Bodies

[Bbarn]

Has anyone used one of the new RF-S lenses on an EOS R series full frame body?  I'm wondering how the IS and Focus/Control ring functions are controlled with no switches on the lenses. Doesn't seem clear in the full frame body manual since it's a new scenario (since all the FF lenses have lens switches).

[shadowsports]

This is possible, but not something I would consider.  You lose much benefit of the FF sensor.  Your image will also be smaller since a RF-S lens will use a much smaller area in the center of the sensor.      

[Tronhard]

Totally agree with Rick.  If you put an RF-S lens on a FF body, you will reduce your sensor capacity by a factor of over 2.5: thus your R5, which would normally be 45 MP will be reduced to 17 and the R6 @ 20MP will be reduced to just under 8MP.  It's in the relevant camera manuals.

[Bbarn]

Looks like Canon needs to step up their game in this community.  Can't get an answer to a simple product question.

[Tronhard]

We are answering your question but the answer is not as simple as you might want.
So, you can physically connect the RF lens to your FF R body  BUT:
It will reduce the effective resolution of the output by a factor of 2.56 because the lens is designed for a smaller sensor and will not fill up all of the area of the larger FF sensor, so the camera will automatically go into crop mode and reduce the sensor to correct this.   It is clearly explained in the manuals for the cameras if you choose to investigate that.

[Bbarn]

My questions were regarding control/focus ring and IS functionality of RF-S lenses on full frame bodies.  Neither of those questions have been answered.

[Waddizzle]

I would suggest downloading a copy of the full user guide for one of the crop sensor bodies or lenses to see how those bodies handles it. 

[Bbarn]

Had to contact Canon CS directly to get the answers.  According to them, when an RF-S lens is attached to a FF body two additional menu items are enabled.  One allows setting the lens ring function, the other permits IS to be turned on or off.  So those additional menu items replicate the IS and Focus/Control switches present on full frame lenses (but absent on RF-S lenses).

[ebiggs1]

"Has anyone used one of the new RF-S lenses on an EOS R series full frame body?"

My question is why? Why do that at all?

"Looks like Canon needs to step up their game in this community."

This isn't a forum for Canon employees to answer questions. It is a User based forum with replies from Canon product owners and users. Canon USA just maintains it.

[ebiggs1]

"We are answering your question but the answer is not as simple as you might want."

A lot of the time, people get an answer but it is not the answer they want or like. But it is the answer nevertheless.