The Nikon SB-910 Speedlight is Nikon's flagship flash unit--the most advanced in the Speedlight range. The SB-910 advances Nikon's lighting mastery by providing easy operation and menu navigation, with a newly simplified graphic user interface (GUI). A dedicated Menu button with quick access to custom settings also simplifies the flash operation. The improved thermal protection system prevents overheating during rapid firing by automatically slowing down the recycle time rather than shutting down the flash. Hard filters for fluorescent and tungsten lighting are included, and the flash automatically changes the camera's white balance to match the filter in use. The automated zoom head covers 17mm to 200mm lenses (in 35mm/FX format), and can cover this range in just 1.2 seconds. This flash lets you select from three light distribution patterns: Standard, Center-weighted, and Even. It will also automatically detect if it is connected to a DX or FX format camera, and adjust itself accordingly. The SB-910 can work as a stand-alone flash, or as part of a wireless group, either in Commander mode or as a slave (remote). The i-TTL system in this flash supports Advanced Wireless Lighting and versatile functions for up to four groups of Speedlights, with 3 remote i-TTL Speedlight groups controlled through the master SB-910. i-TTL Balanced Fill-Flash flash control employs Nikon's Advanced Data Communication System. This system provides an improved method for the monitor pre-flash and wireless operation that marks an evolution in higher precision--it forms the core of the Creative Lighting System. Observação! Please note that the SB-910 is only fully compatible with DSLR cameras that support i-TTL operation. With older cameras that use the D-TTL mode, only [A] Auto mode (non-TTL) is available. Multiple Flash Exposure Modes i-TTL Balanced Fill-Flash with Nikon cameras that support i-TTL (e.g. D3, D700, D200, etc.) [AA] Auto Aperture Flash [A] Auto Aperture Flash with many film SLRs, including the Nikon N55 (F55) and FM10 [M] Manual Flash Advanced Thermal Protection Advanced thermal protection system slows the flash recycle time, rather than simply shutting down to prevent overheating Bounce Capability Flash head tilts down to 7° or up to 90° with click-stops at -7°, 0°, 45°, 60°, 75°, 90°. Flash head rotates horizontally 180° to the left and right with click-stops at 0°, 30°, 60°, 75°, 90°, 120°, 150°, 180° Guide Number 111.5'/34 m (at ISO 100, 35mm zoom head position, in FX format, standard illumination pattern, 68°F/20°C) to 157.5'/48 m (at ISO 200, 35mm zoom head position, in FX format, standard illumination pattern, 68°F/20°C) i-TTL Intelligent i-TTL system supports Advanced Wireless Lighting and versatile functions for up to 3 remote i-TTL Speedlight groups controlled through a master SB-900 or with the "Commander" function of compatible cameras. 3 Light Distribution Patterns Allows you to improve the light quality by selecting Standard for general illumination, Center-weighted for portraits, or Even for groups and interiors. Flash Compensation -3.0 EV to +3.0 EV in increments of 1/3 steps in i-TTL auto flash, Auto Aperture flash, Non-TTL auto flash and Distance-priority manual flash modes Flash Duration 1/880 sec. at M 1/1 (full) output 1/1100 sec. at M 1/2 output 1/2550 sec. at M 1/4 output 1/5000 sec. at M 1/8 output 1/10000 sec. at M 1/16 output 1/20000 sec. at M 1/32 output 1/35700 sec. at M 1/64 output 1/38500 sec. at M 1/128 output Minimum Recycling Time 2.3 sec. (approx.) with Ni-MH (2600 mAh) batteries 3.0 sec. (approx.) with Oxyride (1.5V) batteries 4.0 sec. (approx.) with Alkaline-manganese (1.5V) batteries 4.5 sec. (approx.) with Lithium (1.5V) batteries Mixed Exposure Modes Individual flash mode settings ([TTL], [AA], [A] and [M]) are available for each of the four groups (including master controller) for easy total lighting control based on the brightness of the subject and not simply on general output ratios for each group. FV Lock Flash Value Lock allows photographers to change the composition or zoom for the shot while maintaining desired lighting of the subject. Distance Priority Manual Flash Mode User can set the distance and aperture, and the SB-900 automatically sets the power output, a great feature for manual flash [M] shooting at weddings and for product shots. Colored Gels Allows modification of flash output to match background scene, especially useful for digital cameras where "white balance" can be controlled. Included are Tungsten and Fluorescent adjustment filters. Color Gel Filter Identification Flash automatically identifies mounted color gel filters and adjusts the camera's auto white-balance setting with select Nikon digital SLR cameras. Flash Tube Overheat Protection Includes a built-in thermal sensor that protects the flash-tube from overheating during sustained high-speed bursts. Wireless Flash Modes Master Master (RPT) Off Remote SU-4 AF-Assist Illuminator The SB-910 provides improved AF assisting accuracy by being able to cover all 51 AF points with the D3, D700, and D300 (as of 7/2008), and with wider coverage from 20-105mm. Other Functions Firmware update ISO sensitivity setting Key lock Recalling the underexposure value in the TTL auto flash mode Resetting the settings Improved Thermal Cut-out LCD Large easily read illuminated LCD panel.