Manual - Olympus MACRO FLASH SYSTEM Instructions Manual

<MANUAL>
In this mode, the flash is emitted according to the light intensity setting.
MACRO FLASH CONTROLLER
FC-1
LIGHT
RATIO GN/
Light intensity setting
How to determine the lens iris (F), light intensity or guide number (GN)
Since the distance to the subject is very short and the shooting magnification is very high in
Macro shooting, the light intensity is lower than would normally be the case with the lens iris
(F) setting. This is because the light intensity for the lens iris is based on a distance setting of
infinity.
The F-number at this time Is referred to as the effective F-value, which is variable depending
on the shooting magnification and lens type. In consequence, the above facto should be taken
in consideration when determining the flash light intensity and lens iris in the MANUAL mode.
1.
When using an Olympus Four Thirds System SLR camera:
• Check the light control range of the lens used and set the combination of the lens iris (F) and
light intensity ratio according to the shooting distance (page 24).
• If optimum exposure cannot be obtained, take some test shots and adjust the lens iris, light
intensity ratio and other conditions as required.
2.
When using any other camera:
• Take some test shots and set the lens iris (F) and light intensity ratio as required.
1.
The control panel shows the light intensity ratio.
Light intensity ratio: Ratio of the current light intensity with
MODE
respect to the full flash light intensity.
LAMP
* The light intensity ratio display can be changed to the guide number
AUTO
CHECK
(GN) display in the Custom Setup operation (page 48).
TEST/
CHARGE
2.
Turn dial A to set the desired light intensity ratio.
POWER
The available light intensity ratios are 1/1, 1/2, 1/4, 1/8,
1/16, 1/32, 1/64, 1/128 and 1/256.
Guide numbers (GN) and light intensity ratio
Light inten-
sity ratio
GNm
GNft
1/1 1/2 1/4 1/8 1/16 1/32
11 8.0 5.6 4.0 2.8
36 26 18 13 9.2
1/64 1/128 1/256
2.0 1.4 1.0 0.7
6.6 4.6 3.3 2.3