Zhumell Rangefinder RF645 - Manual (Page 22)

22
4. Other Features 4-3 Electronic flash photography
4-3 Electronic Flash Photography
Equipped with a lens shutter system, the Bronica RF 645 features flash
synchronization at all shutter speeds. Connect an electronic
Speedlight unit to either the hotshoe or the sync terminal located at
the front of the camera. When the dedicated Bronica Speedlight RF
20 is mounted on the hotshoe, vital data such as film speed, set lens
aperture setting and exposure compensation factor will be transmit-
ted between the flash unit, the camera body and the lens, to control
the flash exposure correctly.
1. Automatic Shutter Speed Adjustment.
Provided that the shutter speed dial is set to "P" (Program AE mode),
the shutter speed is automatically set at 1/60 second for the 45mm
and 65mm lenses and the 1/90-second or faster in accordance with
the program line for the 100mm lens as the Speedlight RF 20 com-
pletes its cycle.
Note: The shutter speed is not automatically adjusted if the camera is
in the Aperture-priority AE mode or the manual exposure control
mode. Care should be exercised to avoid picking up camera shake if
the unit is set to a slow shutter speed.
2. Automatic Lens Aperture and Film Speed Settings
Through dedicated electronic contacts on the hotshoe, the film speed
and the lens aperture information are communicated to the
Speedlight RF 20. The transferred data calculates the effective shoot-
ing range of the Speedlight RF 20 and displays the result on the LCD
panel to prevent exposure control mistakes that are common in flash
photography. Unlike most external flash metering systems, the
Bronica RF 645 / Speedlight RF 20 combination does not place any
limitations on lens aperture selection in flash photography. This
unlimited utilization of the lens aperture is extremely effective in the
adjustment of the distance range and depth of field control in flash
photography.
3. Manual Flash Exposure Control
The Bronica Speedlight RF 20 controls the flash light intensity manu-
ally in six steps from 1/1 to 1/32 in one-stop increments. Apply this
manual flash exposure control for accent flash illumination, e.g.: to
highlight a model's eyes, to illuminate the subject with constant flash
power regardless of the ambient illumination or to illuminate a sub-
ject located at a specific distance. The set lens aperture and the prop-
er photographing distance range displayed on the LCD panel of the
Speedlight RF 20 are very useful in determining the manually con-
trolled flash exposures.