I'd just get her conditioned to it...to find out that it is harmless. You could put some yummy treats on the floor next to it, then try holding it in your hand while sitting down and giving her a belly rub, affection, treats, whatever....so she is always associating the camera's presence with a really nice time. You could even set it near her food bowl while she eats. Gradually get so you can move your hand with the camera in it while she's getting all the nice things and just basically make it into an "appendage" of your arm that she sees often. Then move onto trying to hold it up the way you do when you take pictures and if she looks at you without that lowering of the head, tell her "good!" And toss her a hunk of steak or something. Then advance onto clicking it, taking a picture. Do that over a week's or two week's time and see how she does.
Oh yeah....the flash. Well, you could advance to that after all the other getting use to of the camera. You could make it flash at a distance and a little protected so it doesn't get her straight in the eyes at first. Flash = goodies and praise. If she looks frightened, don't praise her. Just use your judgement. She should get use to it if you flash it several times a day from a little ways off from her, and then gradually come closer.