Maximum-Aperture Scale - Nikon Nikkormat FT2 Instruction Manual

Maximum-Aperture Scale
The above adjustment can be confirmed by looking at
the maximum-aperture scale on ring with the coupling
pin. The scale has a range from f/1.2 to £/5.6. For
example, if the 28mm £/2.8 lens is mounted on the
camera, the red index mark should fall opposite 2.8.
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