Nikon D3S User Manual page 217

D
Notes on Optional Flash Units (Continued)
The SB-900, SB-800, SB-600, and SB-400 provide red-eye reduction in
red-eye reduction and slow sync with red-eye reduction modes, while
the SB-900, SB-800, SB-600, and SU-800 provide AF-assist illumination
when the conditions for AF-assist illumination are met. When used with
AF lenses with focal lengths of 17–135 mm, the SB-900 provides AF-
assist illumination for all focus points; note, however, that autofocus is
available only with the following focus points:
17–19 mm
When used with AF lenses with focal lengths of 24–105 mm, the SB-800,
SB-600, and SU-800 provide AF-assist illumination to assist autofocus for
the following focus points:
24–34 mm
In programmed auto, the maximum aperture (minimum f-number) is
limited according to sensitivity (ISO equivalency), as shown below:
200 400
4.8 5.6
For each one-step increase in sensitivity (e.g., from 200 to 400), aperture
is stopped down by half an f-stop. If the maximum aperture of the lens
is smaller than given above, the maximum value for aperture will be the
maximum aperture of the lens.
D
Use Only Nikon Flash Accessories
Use only Nikon flash units. Negative voltages or voltages over 250 V
applied to the accessory shoe could not only prevent normal operation,
but damage the sync circuitry of the camera or flash. Before using a
Nikon flash unit not listed in this section, contact a Nikon-authorized
service representative for more information.
20–105 mm
35–49 mm
Maximum aperture at ISO equivalent of:
800 1600
6.7 8
106–135 mm
50–105 mm
3200 6400
9.5 11
12800
13
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