Olympus CAMEDIA C-4040 Zoom, Справочное руководство

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179
External flash (Cont.)
Chapter 11
Compatible commercially available external flashes
When selecting an external flash, use products which meet the
following basic conditions.
(1) Some flashes available on the market operate with a high voltage synchro
terminal. If one of these is used, it may not function normally. Contact the
manufacturer of the flash you are using concerning the specifications of
the flash's synchro terminal.
(2) Some flashes available on the market have the polarity of the synchro
terminal reversed. In this case, even if the flash is connected, it will not
fire. Contact the manufacturer of the flash for more information.
(3) Exposures when using an external flash require that adjustments be
made on the external flash unit.
If an external flash is used in the Auto mode, match it with the F value and
ISO sensitivity settings on the camera.
(4) Even if the auto F value and ISO sensitivity of the external flash are set to
the same conditions as those on the camera, depending on the
photographic conditions, it is possible that the correct exposure may not
be obtained anyway. In such a case, adjust the auto F value or ISO value
on external flash unit or calculate the distance in the manual mode and
use it that way. However, generally, the auto F value and ISO value can
only be adjusted 1 step and beyond that, exposure compensation cannot
be made. (Exposure compensation in the camera is made invalid in
external flash photography.)
(5) Use a flash which is capable of covering an illumination angle for a 35 mm
or larger lens when calculated for 35 mm film. However, in close-up
photography with the lens on the wide setting, the bottom of the image
may not expose correctly. The ideal is to have a wide angle adapter to fit
on the flash and spread the illumination angle so it is wider.
(6) Use a flash unit with a flash time of 1/200 sec. or less when using the
flash at full strength. For devices with a long flash time, such as a ring
flash, a portion of the light emitted will not contribute to the exposure.
(7) If a flash unit or other accessory with additional communications
functions other than the FL-40 is used, it may not only fail to
function normally, but may also cause damage to the camera’s
circuitry. Do not use such a device.