Bellows Focusing Attachment, Extension Rings; And Focusing Unit; Preset Lenses; Auto Lenses Without Coupling Prong - Nikon Photomic FTN Finder Instruction Manual

Bellows Focusing Attachments, Extension Rings and Focusing
Unit
To determine exposure, select the desired shutter speed and
stop down the lens manually until the needle centers.
Preset Lenses
Use the same procedure as above for lenses having preset
diaphragms, such as the PC-Nikkor 35mm f/2.8.
Auto Lenses Without Coupling Prong
Some lenses like the Zoom-Nikkor Auto 200-600mm f/9.5
have an auto diaphragm but no coupling prong. Use the
depth-of-field preview button to stop down the lens until the
needle is centered.
Reflex-Nikkor Lenses
The Reflex-Nikkor 500mm f/8, IOOOmm fill and 2000mm
f/11 lenses have no aperture diaphragm. Adjust the shutter
speed until the needle is ceniered.
Note: Since focusing may be difficult or impossible at small
apertures due to image darkening on the screen, first open
the lens to full aperture to focus. Then determine the correct
exposure by the stop-down method.
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