Pentax MZ-60 manual Advanced Operation for the BUILT-IN Flash

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ADVANCED OPERATION FOR THE BUILT-IN FLASH

4.Metered Manual Mode

•When using the built-in flash in the Metered Manual Mode, any combination of aperture and shutter speed slower than 1/100 can be set. In this mode, the exposure of the background can be controlled by the manual exposure while the flash properly exposes the foreground subject.

1.Calculating the flash effective range according to the camera- to-subject distance.

Maximum flash distance = Guide Number ÷ Selected aperture Minimum flash distance = Maximum flash distance ÷ 5*

✍MEMO

•When the distance to the subject is less than 0.7m (2.3ft), the flash cannot be used. If the flash is used less than 0.7m, it causes vignetting in the picture corners, light is distributed unevenly and the picture may be over exposed.

•*The value 5 used in the formula above is fixed value applied to the built-in flash in this camera.

The guide number (GN) depends upon the film speed used as shown below.

ISO25	GN5.5		ISO200	GN15.6
ISO50	GN7.8		ISO400	GN22
ISO100		GN11

Exp. 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 in this camera

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