Nikon F3AF instruction manual Duplication work and photomicrography, Slide with continuous

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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-aidoperation 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
	Photographs and
	pictures with continu-
	ous gradation
Copy		Full·aperture
work	Documents and	or stop-down
	drawings of high
	contrast
	Slide with continuous
	gradation
Slide		Stop·down
duplication	Slide of documents and
	drawings photographed
Photomicrography	Prepared specimen	Stop-down

Exposure

compensation

Compensation not necessary

Approx . +t to +2 stops for black letters on white background: approx. - 112 to - 1 stop for white letters on black background.

Approx. + 1 to + 2 stops

Approx . +1 ·112 to +2,112 stops for black letters on white back· ground

oto approx. -112 stop for white letters on black background

Approx. + 1 stop

Required accessories

Micro·Nikkor 55mm 112.8: Cable release

Micro·Nikkor 55mm 112.8: Nikon Slide Copying

Adapter PS·6: Nikon Bellows

Focusing Attachment PB·6 :

Cable release

Microflex PFX

Remarks

For high'contrastsubjects, use of an t8 %

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.

When using Nikon Slide Copying Adapter PS·6, set the flood lamp 30cm away from its opal plate.

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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