Depends on the camera, and on the bulb(s) you're running.

Check out Mand's pics... many of them have those black lines over it. I'm guessing it's because the camera CCD sensor more or less synchronizes with the bulbs' "frequency"... and we get the lines.

When I say 'more or less', it's that this is just my 20 second judgement on the situation... so, NO, I haven't done rigorous scientific testing to my theory. Take it or leave it, as is.
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Dragon,
Try what Hungry suggested.... try playing with the camera's settings.
Or, snap pics with the HIDs OFF...

Let us know how it goes,