Sat Nov 17, 2007 9:14 pm
Basically it's the inverse square law... double the distance from the flash you loose 4 times the light.
Subject is close so it gets lots of light... enough to be correctly exposed
Background... is ... well in the background, way away from the flash and so gets little light.
what you need to do is either shoot in manual mode and set the shutter to stay open longer than the default (usually 1/60th. sec) flash mode shutter speed. this will allow enough light through from the background and the flash will still illuminate the subject. Try starting at 1/60 and increase it a stop each time (60 30 15 7).
Although the flash will generally "freeze" the foreground subject you might want to change your camera's flash sync to second curtain.
Otherwise you can use the scene mode for night portrait - does the same thing though you might find it disables some other settings (don't know Nikon SLR menus - maybe stop you from shooting in RAW?)
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