Nikon D2H User Manual page 121

AF-Assist for Multi-Area AF
The SB-800 features AF-assist illumination linked to the D2H focus areas,
allowing autofocus to be used even at night, regardless of the subject's posi-
tion in the frame. AF-assist illumination can be used in all AF-area modes,
including single-area AF, dynamic-area AF, group dynamic-AF, and dynamic-
area AF with closest-subject priority. If the subject is poorly lit, the AF-assist
illuminator will light automatically when single-servo AF is used in combina-
tion with an AF-Nikkor lens (if a lens with an angle greater than 35 mm is
used, the illuminator may not light if the focus area at the left or right edge
of the frame are selected).
i-TTL Flash Control
When used with the D2H and set to TTL, the SB-800 automatically uses one
of the following types of i-TTL fl ash control:
Flash control
Speedlight emits series of nearly invisible prefl ashes (monitor pre-
fl ashes) immediately before main fl ash. Prefl ashes refl ected from
objects in all areas of frame are picked up by fi ve-segment TTL fl ash
control sensor or 1,005-pixel RGB sensor and are analyzed in com-
bination with information from matrix metering system to adjust
i-TTL Balanced
fl ash output for natural balance between main subject and ambi-
Fill-Flash for
ent background lighting. When type G or D lens is used, distance
Digital SLR
information is included when calculating fl ash output. Precision of
calculation can be increased for non-CPU lenses by providing lens
data (focal length and maximum aperture;
able when spot metering is used.
Flash output adjusted to ensure main subject is correctly exposed;
brightness of background is not taken into account. Recommended
Standard
for shots in which main subject is emphasized at expense of back-
i-TTL Flash for
ground details, or when exposure compensation is used. Standard
Digital SLR
i-TTL fl ash for digital SLR is activated automatically when spot meter-
ing is selected.
Description
124–127). Not avail-
109