Nikon F4 Body Only, F4S instruction manual Diopter Adjustment Knob, Eyepiece Shutter Lever

Diopter Adjustment Knob

This knob enables near- or farsighted photographers to adjust eyepiece diopter within a continuous range of from -3 to +1. Pull the knob and rotate it to either direction until focused image appears sharp, then push back. For diopters beyond this range, Nikon eyepiece correction lenses for F3HP are recommended.

Eyepiece Shutter Lever

During self-timer operation, in automatic exposure modes, use the eyepiece shutter which prevents light from entering the eyepiece and adversely affecting the automatic exposure meter reading. Just turn the lever to the left to close the shutter. The eyepiece shutter is painted red to provide a visual reminder that it'sin use.

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