Nikon s i-TTL (intelligent through-the-lens) flash system meters every exposure, setting the Nikon Speedlight s output to the precise level needed to balance the scene s ambient light.Milliseconds before the main flash, Nikon Speedlights emit a monitor pre-flash, which reflects off every object in the frame, sending to the five-segment i-TTL flash sensor and RGB sensor the data about the scene s available light and shadow areas, subject distance, reflectance and color temperature. This information, along with data from the Matrix metering system, is analyzed to adjust the flash s output for the most balanced background-to-foreground exposure possible. All of this complex processing happens in a fraction of a second, before each exposure, to provide unprecedented levels of flash precision and performance.
Similar to Canon’s “E-TTL”, Nikon’s new flash exposure system is used on the new D70 DSLR and SB-600 and SB-800 Speedlights.
Nikon s i-TTL (intelligent through-the-lens) Balanced Fill-Flash automatically balances the output of the Nikon Speedlight and the scene s ambient light.Immediately before the main flash goes off, the Speedlight fires a series of monitor pre-flashes, which convey Information about the scene s lighting to the camera. Combined with information from the camera s 3D Color Matrix metering system, the information is analyzed to adjust flash output to balance the scene s ambient light.All of this complex processing happens in a fraction of a second, before each exposure, to provide unprecedented levels of flash precision and performance.