White Balance Drifting with Fast Shutter Speeds

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I want to create the "Saving Private Ryan" look with DVX100a. So I switch the cam into fast shutter speed mode (24pA) and the white balance starts to drift from orange to red to violet to blue and so on. It continually cycles thrue the entire range, non-stop. This happens with speeds from 1/250 and up. Below that it appears fine. I had the same problem years ago with the XL1s while shooting a wedding. After banging on the cam for awhile it stopped.

Why does this happen and how do I fix it? :shocked:
 
The banging on the camera idea seems to be more cathartic than curative, but hey, it’s your camera.

Seriously, this makes little sense to me. What I would do to test this theory is shoot a chromatically neutral object (a gray card, chip chart, piece of beadboard) and see if I can reproduce this effect. Since you relate it happening at shutter speeds above 1/250 of a second and shorter, is there a correlation between either the intensity and / or the interval and the higher shutter speeds? Expressed another way, does it happed to a greater extent or more frequently if you really push the shutter speed up (perhaps to 1/1000 of a second)?

The only plausible explanation that I can offer would be that there may be a misalignment (electrical) between the 3 different CCDs causing one to have a comparatively shorter acquisition window than the other 2 which could lead to a shift in balance.

OK, now you have got my interest. Can you reproduce this phenomenon every time you try this setup?
 
It sounds like you're under fluorescent lights to me. When using the shutter especially at higher speeds, Fluorescents, especially office flo's (I don't think Kino's have this problem) will cycle the white balance from blue to orange and back. I believe it has to do with the way the flo's produce light as they flicker and are not continuous like tungsten lights. This should not be a problem outdoors, if it is, then you have a larger problem.
-Ryan
 
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