Nikon F25B manual

Extreme Low-Light Metering

The meter built into the Niko~ F2SB camera is capable of metering low-light levels requiring slow shutter speeds of up to 10 seconds. To meter at low-light levels, perform the following: Set the lens' aperture ring to the desired aperture setting, and the shutter-speed selector to "B"; then, depress and hold the shutter-speed dial lock and turn the selector until the center LED exposure indicator (0) illuminates to indicate correct exposure. Having set the selector, read off the number on the ex tra- long exposure scale and set the camera's self-timer for the indicated value; then, set the T-L fingerguard to "T" and depress the shutter button to make the exposure. When performing low-light metering, be sure to block the entry of stray light into the viewfinder by closing the eyepiece shutter or by continuously viewing through the finder. (Refer to accompanying photos for details.)

Time Exposures

To make an exposure longer than 10 seconds, set the shutter-speed selector to "B" and turn the T-L finger- guard to "T" as described in "Extreme Low-Light Meter- ing." Advance the film and press the shutter-release button to open the shutter. As long as the fingerguard remains set to "T," the shutter will remain open. When returning the fingerguard to the normal center position to close the shutter, be careful not to move or shake the camera, as a blurred image may result.