The Nikon Creative Lighting System (CLS)

Flash Mode Selection for Optional Flash Units

The flash mode for optional flash units can be selected in the same way as the flash mode for the built-in flash, namely by holding the M (Y) button and rotating the main command dial.

Modeling Illumination

CLS-compatible flash units emit a modeling flash when you press the control to which Modeling flash has been assigned using Custom Setting f1 (Custom control assignment). This feature can be used with Advanced Wireless Lighting to preview the total lighting effect achieved with multiple flash units.

Using FV Lock with Optional Flash Units

FV lock is available with optional flash units (0 CLS-Compatible Flash Units) in i-TTL and (where supported) monitor pre-flash qA and monitor pre-flash A flash control modes (see the manual provided with the flash unit for more information). Note that when Advanced Wireless Lighting is used to control remote flash units, you will need to set the flash control mode for the master or at least one remote group to TTL, qA, or A.

Metering

The metering areas for FV lock when using optional flash unit are as follows:

Notes on Optional Flash Units

Refer to the flash unit manual for detailed instructions. If the flash unit supports CLS, refer to the section on CLS-compatible digital SLR cameras. The D7500 is not included in the “digital SLR” category in the SB-80DX, SB-28DX, and SB-50DX manuals.

If an optional flash unit is attached in shooting modes other than j, %, and u, the flash will fire with every shot, even in modes in which the built-in flash can not be used.

i-TTL flash control can be used at ISO sensitivities between 100 and 12800. At values over 12800, the desired results may not be achieved at some ranges or aperture settings. If the flash-ready indicator (M) flashes for about three seconds after a photograph is taken in i-TTL or non-TTL auto mode, the flash has fired at full power and the photograph may be underexposed (CLS-compatible flash units only; for information on the exposure and flash charge indicators on other units, see the manual provided with the flash).

In i-TTL and auto aperture (qA) flash control modes, the flash compensation selected with the optional flash unit or the Flash control option in the photo shooting menu is added to the flash compensation selected with the M (Y) button and command dial.

When an SC-series 17, 28, or 29 sync cable is used for off-camera flash photography, correct exposure may not be achieved in i-TTL mode. We recommend that you select standard i-TTL fill-flash control. Take a test shot and view the results in the monitor.

In i-TTL, use the flash panel or bounce adapter provided with the flash unit. Do not use other panels such as diffusion panels, as this may produce incorrect exposure.

The SB-5000, SB-910, SB-900, SB-800, SB-700, SB-600, SB-500, and SB-400 provide red-eye reduction, while the SB-5000, SB-910, SB-900, SB-800, SB-700, SB-600, and SU-800 provide AF-assist illumination with the following restrictions:

• SB-5000: AF-assist illumination is available when 24–135 mm AF lenses are used with the focus points shown.

  Focal length	24–30 mm
  	31–48 mm
  	49–135 mm

• SB-910 and SB-900: AF-assist illumination is available when 17–135 mm AF lenses are used with the focus points shown.

  

• SB-800, SB-600, and SU-800: AF-assist illumination is available when 24–105 mm AF lenses are used with the focus points shown.

  Focal length	24–31 mm
  	32–105 mm

• SB-700: AF-assist illumination is available when 24–135 mm AF lenses are used with the focus points shown.

  

Depending on the lens used and scene recorded, the in-focus indicator (I) may be displayed when the subject is not in focus, or the camera may be unable to focus and the shutter release will be disabled.

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

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.

Noise in the form of lines may appear in flash photographs taken with an SD-9 or SD-8A high-performance battery pack attached directly to the camera. Reduce ISO sensitivity or increase the distance between the camera and the power pack.

The AS-15 Sync Terminal Adapter

When the AS-15 sync terminal adapter (available separately) is mounted on the camera accessory shoe, flash accessories can be connected via a sync terminal.

Third-Party Flash Units

The camera cannot be used with flash units that would apply voltages over 250 V to the camera’s X contacts or short-circuit contacts on the accessory shoe. Use of such flash units could not only interfere with normal operation of the camera but also damage the flash sync circuits of the camera and/or flash.