On Fri 2003-11-21T09:09:29 -0500, Arnold Rots hath writ:
Shouldn't you also flip the sign bit?
That's part of the traditional trick.

Yes.
Without that the data value in every pixel would be wrong.
With the BLANK value wrong it was only a few in 10000, and
randomly scattered, in most non-lab images.

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Steve Allen UCO/Lick Observatory Santa Cruz, CA 95064
Voice: +1 831 459 3046 http://www.ucolick.org/~sla
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