Nikon has posted Firmware v5.02 for the Speedlight SB-900 flashgun to correct a bug that sometimes results in overexposure. By resolving this issue, metering precision has been further increased and the number of times the flash fires has also been increased.
The new firmware also improves the SB-900â€™s TTL auto flash characteristics. When the SB-900, set to TTL auto flash mode, is used with a camera supporting the Nikon Creative Lighting System (CLS), flash mode automatically changes to A mode according to camera communication status. That flash mode was previously maintained, but it has been modified so that TTL auto flash mode is restored once the SB-900 again recognizes the camera as a CLS-compatible camera.
To install the update, make sure that the SB-900is attached to a Nikon D3, D300, D700 or D90 digital SLR camera.