Maximum Aperture Indicator
As the lens' aperture ring is turned to the maximum aperture position at the completion of lens/finder coupling and indexing, the finder displays the lens' maximum aperture via the indicator (see figure below). For ex- ample, a lens with a maximum aperture of f/2.8 will cause "2.8" to appear in the finder's maximum aperture indicator when properly coupled. The scale is provided with numbers (and dots for intermediate settings) of from "1.2" to "5.6" as depicted.
Maximum Aperture Scale
5·9_ 4.5
4e- 3.5
2
1.4
1.2
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