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>
> A partial solution can be found in the color CCD cameras that are now
> often found on scopes. Even consumer-grade CCD cameras have fairly
> uniform color response. You can use such a camera to find the color
> of your auto-fluorescence under different excitation conditions.
>
> Images from these camera can tell some surprising tales.  I recently
> detected a poor barrier filter by finding some red areas in a
> fluorescence image that was supposed only to be blue. With a
> monochrome camera, I  would have assumed that all the detected
> photons were blue.
>

However, one must note that the color separation filters in RGB cameras
are fairly broad and not designed for the ultimate in out-of-band rejection.
So if the phenomenon described above is seen, it might be a good idea to
confirm the diagnosis with a spectrophotometer.

--aryeh