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FP High-Speed Sync Flash
Chapter
1
Main Features/Functions
Standard TTL Flash
It is possible to manually select a flash compensation
level instead of having the computer do it automatical-
ly. Simply press the SB-25’s
button to cancel
Automatic Balanced Fill-Flash.
The camera’s computer-controlled TTL flash sensor
detects the total amount of light passing through the
lens and reflected from the film surface. The system
controls flash output so that the combination of ambi-
ent light and flash illumination will result in a correct
exposure.
Under bright-light conditions, the flash is automati-
cally controlled to provide less light; under dim light
conditions, it will produce more light.
This system is not designed to automatically provide
a balance between flash and ambient light; it is limited
to efficient operation in dim-light conditions and is not
recommended for use in very bright lighting condi-
tions. This system does not directly link the ambient
light meter and the flash’s TTL meter.
FP High-Speed Sync Flash: Allows a wider aperture, thus, shallower
depth of field for a blurred background.
“TTL Multi-Sensor” Automatic Balanced Fill-
Flash with F90-Series/N90
After you depress the shutter release button and prior to the
shutter being activated, the SB-25 fires a series of nearly
invisible preflash, or Monitor Preflash.
These preflash are detected by the F90-Series/N90’s TTL
multi-sensor, analyzed for brightness and contrast, then
integrated with distance information from the lens (D-type
Nikkor) and other exposure control information for a bal-
anced fill-flash exposure.
3D Multi-Sensor Balanced Fill-Flash
can be performed
with any built-in metering system, and is most effectively
used to achieve correct exposure in scenes that include:
• A mirror, white wall or other surface with extremely high
reflectivity
• Obstacle(s) in front of subject you wish to avoid
• Sunlight
• Subject against an “infinite” background (empty sky,
clouds, etc.)
With non-D-type AF or AI-P Nikkor lenses,
Multi-Sensor
Balanced Fill-Flash
will be performed. Although the TTL
multi-sensor does not process distance information, the
advanced sensor system generally provides superior results
to Matrix Balanced Fill-Flash.
3D Multi-Sensor Balanced Fill-Flash photography: particularly
effective for subject standing against a shiny object.
The SB-25 is capable of flash synchronization at shutter
speeds of 1/250 sec. or faster when used with the new F90-
Series/N90. Unlike other flash synchronization methods, the
flash consecutively emits light at an extremely rapid cycle
and exposure begins with the opening of the front (first) cur-
tain and ends with the closing of the rear (second) curtain.
SB-25_En 03.1.14 8:18 PM Page 12
Summary of Contents for SB-25
Page 1: ...Instruction Manual E Autofocus Speedlight 25_En 03 1 14 8 18 PM Page 1 ...
Page 4: ...Chapter 1 Introducing the SB 25 Autofocus Speedlight 25_En 03 1 14 8 18 PM Page 6 ...
Page 10: ...Chapter 2 Before Flash Shooting 25_En 03 1 14 8 18 PM Page 18 ...
Page 49: ...Chapter 4 Flash Shooting Applications 25_En 03 1 14 8 18 PM Page 96 ...