Digital BW, The Print

I read in the PDN Forum an explanation about the inability to 
turn off the internal flash on the Nikon 5000.  It was explained 
that when a flash or radio slave is attached to the hot shoe, the 
internal flash is automatically disabled, however it continues to 
fire a very reduced burst.  The explanation the users on that 
forum received from Nikon was that this is only a pre-flash, and 
that its power would not affect overall exposure.  Some testing 
was done by a user and he came to the conclusion that this was 
indeed what was happening, because as he measured it, the 
internal flash was firing at only 1/10 of what was necessary to 
create a proper exposure.
      Thought you might find that interesting.

Justin Smith