30
Adjustments for Focusing Screens
Light transmission properties vary somewhat with focusing
screen type, thus occasionally requiring exposure correction
to compensate for the combined effects of the lens/screen com-
bination in use. The numbers listed in various blocks of the
table on the opposite page denote the amount of correction
necessary in f/stops. To adjust the camera’s finder for the in-
dicated f/stop correction, lift and turn the ASA film-speed in-
dex ring until the ASA value for the film in use is aligned with
the appropriate mark engraved on the ring. In the example
figure shown, ASA 100 is aligned with the—1/2 mark to pro-
vide the correction required when using the Type C screen
with the Nikon F2AS Photomic camera and the Fisheye-
Nikkor 6mm f/2.8 lens, as indicated in the table. (When “O”
is indicated in the table, no compensation is requ ired.)
= Exposure measurement via full-aperture method.
= Exposure measurement via stop-down method.
= Exposure measurement not possible; lens/screen
combination permits only focusing operation.
Blank space indicates lens/screen combination cannot be used.
EXPOSURE COMPENSATION ADJUSTMENT
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