Nikon SB-800 TTL AF Shoe Mount Speedlight, Guide Number at ISO 100, m/ft. 56/184 at 105mm Setting, USA Warranty.

The i-TTL Flash Control system supports automatic balanced fill flash that delivers outstanding results as well as new creative possibilities. i-TTL Balanced Fill-Flash flash control employs Nikon's Advanced Data Communication system to introduce an improved method for the monitor pre-flash and wireless operation that marks an evolution in higher precision over Nikon's acclaimed D-TTL Balanced Fill-Flash control system and forms the core of the Creative Lighting System. The Nikon Speedlight SB-800 makes Advanced Wireless Lighting (= wireless multiple flash) as easy to use as a single on-camera speedlight, inviting professional and advanced amateur photographers to explore the unlimited creative possibilities. Advanced Wireless Lighting lets you divide SB-800 Speedlights into 4 groups, including the Master and 3 remote i-TTL speedlight groups, to achieve total lighting control. All groups can be controlled from the Master, including independent flash mode ([TTL] / [AA] / [A] / [M]) settings and any-time adjustment of flash output level compensation values for each group. Each of the three remote groups can contain any number of Speedlights, giving photographers full control over how they illuminate the background. With Distance Priority Manual Flash Mode, the photographer can set the distance and aperture, and the SB-800 automatically sets the power output, a great feature for manual flash [M] shooting at weddings and for product shots. The FV Lock (Flash Value Lock) maintains the flash value for correct exposure of the subject while zooming or otherwise changing the composition for a shot, so photographers can concentrate on lighting a particular subject. Auto FP High Speed Sync Mode provides ample fill-in flash when shooting in bright light with fast aperture lenses to achieve effective blur in the background. When the mode is active, the camera automatically uses high-speed flash synchronization to make shutter speeds available that exceed the camera's own flash sync speed. A Modeling Flash allows photographers to visually preview the lighting effects for all groups of speedlights when using Advanced Wireless Lighting to shoot with multiple flash units, a great aid in achieving the exact lighting desired. The SB-800 is also fully compatible with existing Nikon cameras, retaining the same functions as the SB-80DX when used with them. Auto flash control uses D-TTL on Nikon DX Format digital SLR cameras and TTL and Non-TTL Auto Flash on film cameras. Advanced i-TTL requires support for the Creative Lighting System and is currently available only on the D2H. With its ease of use and unlimited creative potential, the Speedlight SB-800 will be welcomed by photographers who want complete, yet simple control over their lighting