I've played with a webcam a little, but not the same as yours.
IIRC, there's driver settings for some webcams that you can set at driver
load, to adjust the brightness/contrast/etc.  I'm guessing that will
disable the "auto-brightness" but it's worth a shot.

On Fri, 19 Jul 2002, Tracy McKibben wrote:

> Anyone here with knowledge of running a webcam under Linux?  Specifically,
> I'm using a DLink DSB-C100 under Mandrake 8.2, using a package called
> Motion to detect movement on the webcam.  All is well, with the exception
> of picture quality, the pictures are VERY dark.  The same camera gives
> very good pictures under Windows, and the clarity is the same under Linux,
> just very dark.  The camera has auto-brightness adjustment, and I've also
> tried turning on the auto-brightness setting in Motion, but no dice.

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