DNotes 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 20–105 mm 106–135 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

35–49 mm

50–105 mm

In programmed auto, the maximum aperture (minimum f-number) is limited according to sensitivity (ISO equivalency), as shown below:

Maximum aperture at ISO equivalent of:

200

400

800

1600

3200

6400

12800

4.8

5.6

6.7

8

9.5

11

13

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 l maximum aperture of the lens.

DUse 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.

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