The problem with the built-in strobe is not the flash, but how you're setting the camera. If you're using full auto, that's what happens. If you use other modes (I'm sure of S, A and M - probably P too) the internal flash will not deploy unless you pop it up. The SB-24 will fire correctly.
The problem with the SB-24 is that you have to set it properly. I don't think it gets aperture or ISO information from the camera, so you have to set those on the flash. Once you do that, the exposure should be pretty close as long as you're not using an extreme focal length. On a DX body, anything in the range from about 20-70mm should be fine, because that is fairly similar to the field of view of the flash's light sensor.
_____ Brian... a bicoastal Nikonian and Team Member
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