EOS

[ianc]

I was looking at the EOS R adapters and noticed that there are 2, one with a control ring and one without. I'm curious to know what the difference between the 2 is and what the control ring does exactly. Is it necessary to drop another $100 on the control ring?

[Waddizzle]

The control rings are programmable.  The new RF series of lenses all have a control ring, which is also programmable.  The control ring on RF lenses have default programming to be an aperture control ring.  I would want an adapter with the control ring.