Focusing is done on the groundglass - either waist level finder or heavy prism made out of Russian T-54 tank armor.
The side distance scale tells you the distance to the subject with various lenses.
Note that what appears to be a distance scale on the front of some lenses is really a movable depth of field scale (see photo).
Also, some lenses have a secondary floating element focus ring, which is set after doing your primary focus (see photo).
I love all these things about the RB67!
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