Quantum Instruments QFX5d-R - Manual (Page 14)

10
8.2.2 Manual mode Qflash Compensation
This procedure will calibrate
Qflash to an
incident light flash
meter you use and trust. Note
that only incident light measure-
ments are reliable for manual
exposure settings.
1. Place the Qflash 10 feet from the incident light flash meter facing
Qflash.
2. The area surrounding the meter and flash should be similar to the
shooting environment you usually work in. For example, in a large hall,
there will be little light bouncing from walls and ceilings. In a small room,
the light meter reading will be increased by whatever bounce occurs
from nearby surfaces. These factors will affect calibration and should be
considered.
3 Turn Qflash on and change the manual power setting to 1/8.
4. Set the film speed on the flash and the flash meter to the same value.
5. Change the F number on the flash until the distance shown in the
display is 10 feet.
6. Fire Qflash. Push the the Option ■ button, until the compensation
display appears.
7. Use the Set G and Up J/ Down L buttons to adjust compensation until
the f/number in the display matches the f the f/number on the meter.
The light output can be increased or decreased by as much as 2 stops
in 1/3 steps.
8.2.3 Auto mode Qflash Compensation
This procedure will calibrate Qflash to a reflected light flash meter you use
and trust. Note that only reflected
light measurements are reliable for
auto exposure settings.
This is because auto mode flash-
es read reflected light from the
scene and subject. In order to
compare those readings to
a meter, the meter must also be
reading the same reflected light.
The reflected light is affected by
the subject and background, and an incident light reading will not typically
provide the same reading (unless the subject is an 18% gray card).
1. Place the Qflash 10 feet from a blank wall. The wall should be larger
than the metering area of the meter, and preferably a wall of continuous
tone (blank wall).
2. Place flash meter next to Qflash, also facing the blank wall. Be sure to
set the flash meter for a reflected reading.
3. Turn Qflash on and change the f/ number to F8.0
4. Set the film speed on the flash and the flash meter to the same value.
QFT5D INSTRUCTIONS 10/5/06 10:27 AM Page 14