bitmaker wrote:
To clarify, 3D multi sensor is the only flash exposure mode that uses focus distance info (and only when D and G lenses are used). None of the other flash exposure modes use distance info for fill flash, so distance then becomes largely irrelevant. To assume that the brightest focus point is the sole variable in the system creating proper fill flash exposure falls short.
Regards,
Greg
Once you tilt the flash head , or as you say use a lens without distance info the difference between TTL/BL and TTL is that TTL acts like centre-weighted metering while TTL/BL finds the brightest object under a focus point reflecting a pre-flash reading , it would make sens to design the system that way to \'find\' the subject .
