Olympus c-755 ultra zoom 入門マニュアル

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External flash (optional)
4
Fl
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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 damage the camera, and/or the 
camera 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 the external flash unit or calculate the distance in the manual mode 
and use it that way. Generally, however, 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 38 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 TTL flash that has additional 
communications functions other than the FL-20 or 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.