Steve B wrote:
Let's say that I change my setting for either aperture, speed, or manual
priority.

I set the aperture for depth of focus, and the camera selects the speed.
I set the speed to freeze motion, and the camera selects the aperture.
I put it on manual, and can set both, even intentionally off if I want to.

Now, the question. I turn on the flash.

Does the camera use the settings I put in, or does it go into control of the
camera, and change any of the settings? I have taken many photos of the

The answer is it will depend on the camera and flash.

If you want complete control of what's really going to happen, use a
"dumb" strobe. Speedlights (an expensive flash attached do you camera)
will chatter back and forth with the camera and try to be "smart". Keep in
mind that "smart" means the end result of softare written by people who
can't even type their spoken language on a keyboard.

The Nikon speedlight system isn't bad- it's just overly complex and poorly
documented.