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Advanced techniques with the built-in flash – Pentax MZ-6 User Manual

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Reducing Red Eye

Red eye occurs in flash pictures when the flash reflects off the eye’s reti-
na. Although red eye cannot be totally prevented, it can be reduced by the
following methods:
• Take the picture in a well-lit place.
• When using a zoom lens, use the wide-angle end and a close distance.
• If you are using an external flash unit, keep it apart from the camera

lens as far as possible.

ADVANCED TECHNIQUES WITH THE BUILT-IN FLASH

This section explains how to calculate the built-in flash’s
effective range and the compatibility with F and FA lenses.

Calculating the flash effective distance according to the

camera-to-subject distance.

Calculate the effective flash range as follows:

For far distances

Guide No. ÷ Current aperture

For near distances Far distance result ÷ 5*

1

*1: This formula using “5” as the divider applies only to the built-in flash.

The flash cannot be used at distances shorter than 0.7 m. Doing so will
result in irregular or obstructed flash coverage and flash overexposure.

Memo

Memo

Memo

Memo

The Guide No. will be as follows depending on the ISO film
speed.

ISO Film Speed

Guide No.

ISO25

5.5

ISO50

7.8

ISO100

11

ISO200

15.6

ISO400

22

With ISO 100 film and an f/2.8 aperture, calculate the
effective flash range as follows:

For far distances

Guide No. 11 ÷ f/2.8 = approx. 3.9 m

For near distances 3.9÷5 = approx. 0.8
The effective flash range is therefore approx. 0.9 m - 4.3 m.

Calculating the flash aperture from the effective flash

range

Use the effective flash range to calculate the flash aperture as follows:

Guide No. ÷ flash range = Flash aperture

If the result is a number (such as 3) that is not a lens aperture value, set
it to the next smaller aperture value (2.8).

Memo

Memo

USING THE BUILT-IN FLASH

STEP UP

FLASH PHO

T

OGRAPHY

MZ-6(E)05 E1/085-094 11/8/02 12:06 PM Page 88