How does the Cobalt detector do it's thing?

	I can imagine several possibilities, each one with its
own  Achilles heal. You could have 3 photo detectors, each
looking for a different primary color. That would work as long
as the optics made sure each detector saw the same object.

	Video cameras are getting pretty cheap but one would need
a computer to read the picture and software to blank out all
parts of the picture but the wire or resistor that was of
interest. Would it even be able to tell the difference between
orange and gold or silver and white?

	Grey is just white that isn't as bright as white. In
fact, with no reference, grey might be somebody else's white.

	Many cables have a predominant color and then a tracer
which is a candy cane spiral of some other color so one would
need to move the detector along the wire to pick up the tracer.
CAT5 cable uses this scheme to identify the pairs. One lead of a
pair is predominantly one color such as brown with a white
tracer and the other lead for that pair is white with a brown
tracer and so forth.

	What you need is a pinpoint detector so that one would
know what one was actually reading.