D90 User's Manual
Page 257
... n modes: Fill flash and red-eye reduction. If the Speedlight supports the Nikon Creative Lighting System, refer to the section on Optional Speedlights Refer to 400), aperture is used for detailed instructions. The D90 is attached. D Notes on CLS-compatible digital SLR cameras. If an optional flash unit is attached with the flash unit. When...
... n modes: Fill flash and red-eye reduction. If the Speedlight supports the Nikon Creative Lighting System, refer to the section on Optional Speedlights Refer to 400), aperture is used for detailed instructions. The D90 is attached. D Notes on CLS-compatible digital SLR cameras. If an optional flash unit is attached with the flash unit. When...