Canon EOS R50 Instruction Manual page 343

3.
Select an option.
Focus distance disp
You can display focus distance when using RF lenses. In focus
distance display, you can select the timing and unit of measurement.
Focal length disp
You can display the focal length of the lens in use.
SA variable amount
You can display the amount of correction set when using lenses
featuring spherical aberration control.
* SA: spherical aberration
300