Nikon AI-S Zoom-NIKKOR 35-105mm f-3.5-4.5 - Manual (Page 16)

INFRARED PHOTOGRAPHY
In infrared photography, the plane of sharpest focus is
slightly more distant than the one produced by visible light.
As a rule of thumb, you can compensate for shift in focus
by referring to the curved red infrared index engraved be­
tween the depth-of-field scale lines on the lens barrel.
After sharply focusing the subject through the viewfinder,
check the focused distance and turn the focusing ring to the
left until the prefocused distance figure is aligned with the
infrared index. Then attach the filter to the lens and take
the picture.
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