There is no such thing as a stupid question - it's just that we specialists have to make up our minds
Just tested it:
1. Set your D80 to manual. Push the flash in.
2. Point at some static object indoors (not too bright) and adjust aperture and/or shutter to have the meter exactly at 0 (a.k.a "zero")
3. Now pop the flash up. My display changes to "-" when i pop up the flash.
Now that's funny. shouldn't the flash add light so the metering should go to "+"? Well, strange things happen: I have my ISO set to auto and that also seems to change, when I popped up the flash. So some nontrivial calculations are going on inside the cam.
When I'm aiming outdoors nothing changes (neither exposure nor ISO). It seems that the cam assumes that the small onboard-flash does not really add to the lighting.
But to make exact judgments, not only look through the viewfinder but also make photos, as the exposure of the cam and flash is real-time controlled, when the flash hits the fan (so to speak).
But for you being so pushy, I'll leave that as a homework for you, TelexStar
Thomas (beware: Nikon-fanboy and moderator!) My Lens Reviews
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