Flash Control; Shutter Speeds Available With The Built-In Flash - Nikon D90 User Manual

Flash Control

The following types of flash control are supported when a CPU lens is used in
combination with the built-in flash or optional SB-900, SB-800, or SB-600 flash units
(pp. 73, 234).
• i-TTL Balanced Fill-Flash for Digital SLR: Flash output is adjusted for a natural balance
between the main subject and the background.
• Standard i-TTL Fill-Flash for Digital SLR: Flash output is adjusted for the main subject; the
brightness of the background is not taken into account. Recommended for shots
in which the main subject is emphasized at the expense of background details, or
when exposure compensation is used.
Standard i-TTL flash control is used with spot metering or when selected with the
optional flash unit. i-TTL balanced fill-flash for digital SLR is used in all other cases.

Shutter Speeds Available with the Built-in Flash

The following shutter speeds are available with the built-in flash when vibration
reduction (VR) is not used.
Mode
i, k, P * , A *
n
o
* Slowest shutter speed at which flash will be used can be selected using Custom Setting e1 (Flash
shutter speed). Flash will still fire at shutter speeds as slow as 30 s when set to slow sync.
Shutter speed
1 1
/ – / s
200 60
1 1
/ – / s
200 125
1
/ –1 s
200
Mode Shutter speed
1
S
1
–30 s , A
M /
200
/ –30 s
200
n
265