Nikon SB-27 instruction manual Thru, ISO film speed and coefficient

thru VI)

4 Set up the diffuser card as shown.

The SB-27's built-in diffuser card is effective for close-up flash operation from 0.3m (1 ft).

—Avoid using the built-in diffuser card for close-up flash operation in non-TTL Auto Flash mode. (You cannot obtain a correct exposure if the diffuser card is set.)

5 Set the camera’s aperture based on the following equation and table.

f/stop ≧

coefficient

flash-to-subject distance (m)

ISO film speed and coefficient

ISO film speed	100 or lower	125–400	500 or higher
Coefficient*	1 (3.3)	2 (6.6)	2.8 (9.2)

*Numbers in parentheses ( ) represent coefficient for foot measurement.

For example, with a subject located 0.5m (1.6 ft) away using ISO 100 film and a bounce flash adapter, this is how you would calculate the aperture:

f/stop ≧	1	＝ 2*
	0.5

* An aperture of f/2 is suggested. We recommend using the smallest possible aperture ( f/2.8 or f/4).

6 Confirm that the ready-light is ON, then release the shutter to fire the flash.

TTL	f t		m
	60		18
A
	30		9
M ISO	15		4
	7	2
	4	1
	2	0.6

If the ready-light blinks for 3 seconds after shooting, see page 40.

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