Nikon Camera F3AF - Manual (Page 102)

ACCESSORIES —continued-
Duplication work and photomicrography
The F3AF combined with the proper accessory enables you to
perform duplication work or photomicrography. In these special­
ized areas of photography, however, focusing should be per­
formed manually using the matte portion of the focusing screen
as autofocus/focus-aid operation is, in most cases, impossible.
In addition, exposure compensation is required because these
areas of photography represent unusual contrast situations.
Shown in the table is the relationship between specific photo
types and proper exposure. Since this is meant to be a guide, in
practice, you should make further compensation by experimen­
tation until you achieve the proper results.
1 ) The exposure compensation values listed below are reference
data obtained when general-purpose film was used. With
color reversal film or microfilm for duplication work, it is
advisable to take additional shots with ± one-stop exposure
compensation as these films have very small exposure
latitude.
2) To avoid vibration, you can make the exposure by turning the
illumination on and off.
3) It is advisable to use a cable release to eliminate camera
vibration.
Subject
Method of exposure
measurement
Exposure
compensation
Required accessories Remarks
Copy
work
Photographs and
pictures with continu­
ous gradation
Full-aperture
or stop-down.
Compensation not
necessary
Micro-Nikkor 55mm f/2.8;
Cable release
For high-contrast subjects, use of an 18%
reflectance gray card in determining exposure
is recommended. With the card, no exposure
compensation is required regardless of whether
the background is black or white.
Documents and
drawings of high
contrast
Approx, -n to - f 2
stops for black letters
on white background;
approx. -1/2 to -1
stop for white letters
on black background.
Slide
duplication
Slide with continuous
gradation
Stop-down
Approx. -)-1 to -t-2
stops
Micro-Nikkor 55mm f/2.8;
Nikon Slide Copying
Adapter PS-6;
Nikon Bellows
Focusing Attachment
PB-6;
Cable release
When using Nikon Slide Copying Adapter PS-6,
set the flood lamp 30cm away from its opal plate.
Slide of documents and
drawings photographed
Approx, +^^M2 to
+ 2-1/2 stops for black
letters on white back­
ground
0
to approx. -1/2 stop
for white letters on
black background
Photomicrography Prepared specimen Stop-down Approx. +1 stop Microflex PFX
Generally, results come out better with more
exposure in photomicrography. The compen­
sation value on the left is only a guide; determine
the compensation value by test shooting.
+ : more exposure -.' less exposure
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