Flash Analyzing Function - Sekonic L-758C Operating Manual

2-5 Flash analyzing function

When measuring flash light, the shutter speed and F stop value (combining ambient light and
flash light: total amount of light) are displayed on the LCD screen and the ambient light and
flash light are each displayed as separate values along with the total amount of light (combined
flash and ambinent) on the analog scale. In addition, the ratio of flash light to the total amount
of light is displayed as a percentage (in 10% steps) at the sametime. The ratio of flash to the
total amount of light is useful when a desired flash to ambient lighting ratio is needed.
< Example >
Under certain conditions, if the flash light output is
60% and the available light output is 40%, the LCD
screen will display the flash measured value on the
analog scale with a faster blinking icon than the total
exposure blinking icon.
1. To emphasize the ambient light (to create a more
natural lighting condition) increase the ratio of
ambient light,(use the Jog wheel ⑤ )by changing
the shutter speed to a slower setting.The ratio of
flash light in the total exposure will be reduced (as
shown in the diagram to the right - 20%).The
analog scale also shows the ambient output to be
about 2.5 stops higher than the flash light output.As
a result,images will exhibit a natural lighting quality
with flash filled shadows without an over powering
presence of flash.
2. To reduce the effect of ambient light decrease the
ratio of ambient light, (use the Jog wheel) by
changing the shutter speed to a faster setting. The
ratio of flash in the total exposure will be increased
(as shown in the diagram to the right – 80%) The
analog scale also shows the flash light output to
be about 1.5 stops higher than the ambient light
output.
Reference:
• Slower shutter speeds allow more available light to reach the film or digital camera sensor,
and faster shutter speeds reduce the amount of available reaching the film or sensor.
• The settings above are made by adjusting the ambient light by the shutter speed. It is also
possible to modify the ratio by adjusting the flash light (when changing the distance between
the flash and the subject or when changing the amount of light of the flash). When using
this method, re-measure each time the flash light is adjusted.
5. Measurement
Percentage of flash in
total exposure
Ambient Flash Measured f stop
(total exposure)
(Display in spot viewfinder)
-27-