Nikon D90 CLS-Compatible Flash Units, 234, Use Only Nikon Flash Accessories, Guide Number

❚❚CLS-Compatible Flash Units

The D90 can be used with the following CLS-compatible flash units: the SB-900, SB-800, SB-600, SB-400, SB-R200, and SU-800.

The SB-900, SB-800, SB-600, SB-400, and SB-R200

The principal features of these flash units are listed below.

	Flash unit
Feature			SB-900 1	SB-800	SB-600	SB-400	SB-R200 2
Guide No. 3		ISO 100	34/111	38/125	30/98	21/69	10/32
		ISO 200	48/157	53/175	42/138	30/98	14/49
Auto power zoom (mm)			17–200	24–105	24–85	— 4	— 5
Wide panel (mm)			12, 14, 17	14, 17	14	—	—
				7 ° down, 90 ° up,			60 ° down (toward
			7 ° down, 90 ° up,		90 ° up, 180 ° left,		lens light axis),
Head rotation			180 ° left/right	180 ° left,	90 ° right	90 ° up	45 ° up (away from
				90 ° right			light axis)

1 If a color filter is attached to the SB-900 when AUTO or N(flash) is selected for white balance, the camera will automatically detect the filter and adjust white balance appropriately.

2Controlled remotely with built-in flash in commander mode or using optional SB-900, SB-800 flash unit or SU-800 wireless Speedlight commander.

3m/ft., 20 °C (68 °F), SB-900, SB-800 and SB-600 at 35 mm zoom head position; SB-900 with standard illumination.

427 mm zoom coverage.

5 24 mm zoom coverage.

SU-800 Wireless Speedlight Commander

When mounted on a CLS-compatible camera, the SU-800 can be used as a commander for remote SB-900, SB-800, SB-600, or SB-R200 flash units. The SU-800 itself is not equipped with a flash.

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.

AGuide Number

To calculate the range of the flash at full power, divide the Guide Number by the aperture. For n example, at ISO 100 the SB-800 has a Guide Number of 38 m or 125 ft. (35 mm zoom head

position); its range at an aperture of f/5.6 is 38÷5.6 or about 6.8 meters (or in feet, 125÷5.6=approximately 23 ft. 7 in.). For each twofold increase in ISO sensitivity, multiply the Guide Number by the square root of two (approximately 1.4).

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