There are a few comparators available, some manual, some automatic.  Some
switch between images quickly making any differences stand out, others
actually display a 'difference image' which highlights differences between
the boards.

The golden image is usually stored electronically - one of the better ones I
have seen in manufactured by Diagnosys and I think was called Viewpoint.  It
actually used a scanner to take an image of the board!!

They have a Web Site at www.diagnosys.com

Neil

Neil Atkinson


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