Pentax 57233 manual Minimum distance of the built-in flash

Example:

If an ISO100 film is used at an aperture of f/3.5, the flash effective distance is obtained as follows:

For maximum distance Guide Number (11) ÷ f/3.5 = 3.14m For minimum distance 3.14 ÷ 5 = 0.63m →0.7m *

*Minimum distance of the built-in flash

Thus, the flash effective distance is from approx. 0.7m to 3.14m.

2.Calculating the aperture according to the camera-to-subject distance

Aperture = Guide Number ÷ Camera-to-subject distance

Example:

If the camera-to-subject distance is 2.5m and ISO 100 film is used, the effective aperture is obtained as follows:

Guide Number (11) ÷ Distance (2.5m) = f/4.4

If the calculated aperture value is different from an indicated f stop, for instance f/4.4, select the next smaller aperture value. (Set at f/4 in this case.)

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BASIC OPERATION	(PREPARATION)
BASIC OPERATION	(SHOOTING)
ADVANCED OPERATIONS
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