Aperture Priority Mode, Flash in low light.

[Boomn4x4]

When I take pictures indoors in aperture priority mode, the exposure meter is always showing under exposed, even if I have the flash turned on. The only time it meters correctly is if I change my flash mode to slow. When I do so, the meter shows proper exposure, but the shutter speed slows considerably.

If I shoot with a normal flash, even though the exposure meter is all the way to the right, the photo doesn't seem over exposed... it seems fine. I'm not sure if I'm doing something wrong, but something tells me that I am... or at least I'm not understanding something.

Why does the camera meter show under exposed when in aperture priority mode, when the pictures come out just fine?

...oh, and I'm shooting a D40

 

[IgsEMT]

When camera meters, it shows you what it SEES. When it fires and I'm assuming you're shooting in TTL, flash puts out the amount of power camera thinks necessary.

Why does the camera meter show under exposed when in aperture priority mode, when the pictures come out just fine?

Same would be if your camera in shutter priority, manual, (not sure program mode) and flash in A, AA or TTL modes.