Vivitar VIV-PRO-648 Camera Flash User Manual


 
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• Automatic flash sync speed control
When the flashgun is ready, your camera will automatically switch it to the flash
sync speed from program mode or or to an aperture-priority mode selected. The sync
speed depends on the camera model and usually ranges between 1/30sec to 1/250sec.
When a flash shot has been taken, an "OK" symbol briefly flashes on the LCD display to confirm
correct exposure.
• Auto-focus "AF" measuring flash
The integrated "AF" red light beam of the flashgun supports the automatic focusing of auto-focus
TTL cameras. When the prevailing light is insufficient for automatic focusing, the flashgun will
project a red light beam onto the object as soon as the camera's shutter is lightly touched. The
camera's auto-focus system then focuses the object by this beam of red light.
• TTL flash control
When you switch on the flashgun, it will set at TTL mode first and the LCD display indicates "TTL".
When the Ready indicator lights up, press the shutter release fully to take the picture. The advanced
programming and computerized circuitry of the fllashgun provides the correct amount of flash light
output according to the camera's exposure measurement through the lens (TTL).
Taking a Picture AF / TTL Operation