Nikon SB-900 - Professional i-TTL flash is compatible with Nikon FX and DX format SLR cameras and includes Nikon's Creative Lighting System. This powerful flash offers photographers a wide range of flash photography options. Three illumination patterns - center-weighted, uniform and standard - provide absolute control over flash coverage, allowing the flash to cover its class-leading auto zoom from 17 to 200mm in just 1.2 seconds. Advanced features include a booster circuit that allows high-speed recharging using AA batteries and built-in thermal protection to warn you of extreme heat. The SB-900 can automatically detect the presence of an incandescent or fluorescent color filter and transmit this information to the camera's white balance setting, and its firmware can be updated via the camera body.