On a new C80, I have the Control Ring in the menus set to adjust Iris. At first when I set this, it worked fine. Then later, it did not. Did I unwittingly change another setting elsewhere that made it so the control ring (not dial, the dials are fine) will not adjust?
I tried with different settings (ISO, WB, etc) and different lenses (Canon RF 50mm f/1.2 L, Canon RF 85mm f/2, and Canon RF 50mm f/1.2 L) to no avail. It just doesn't change a setting. It functions fine when in the menus, or having something selected to change, but not to simply adjust Iris.
