"This subject has probably been thrashed at this point, but I'm still confused. If the purpose of 3DMBFF is to balance flash light with ambient light, then what's the point in using it? This has to be a dumb question, I know, but what exactly do you mean by "balancing" or "matching"? If by "balance", you mean "produce an amount of flash light that's equivalent in brightness to the ambient light" then, surely, the flash light won't be seen (as it's only as bright as the ambient light). Can anybody clarify, please?" A subject can be framed by light without being immersed in it or lit up by it. In other words, the term "ambient light" doesn't always mean a light that is "surrounding" the subject in three dimensions. Sometimes the term is used to describe light in the frame of the picture as seen through the viewfinder. I think of 3DMBFF (3D Matrix Balanced Fill Flash - or just matrix balanced fill flash, for that matter) in terms of background light and foreground light. A subject with a sunset behind them can be completely dark if there isn't a flash to light the foreground. But standard TTL can give perfect exposure on the foreground while at the same time causing the aperture or shutter speed to reset so that the background is very much underexposed. MBFF is designed so that the exposure of the background is perfectly balanced with the light from the flash lighting a subject in the foreground - with neither light overpowering the other. Richard
