Spark is dead on with his comment that the color doesn't make diddly difference to an NVD. Both the red and blue lensed lights are primarily radiating in the visible spectrum, & the gallium arsenide photomultipliers in the NVDs aren't selective about the color of the light, just that it's there. That is why "invisible" laser designators, which emit at wavelengths outside the visible spectrum of the human eye, can be used for targeting with NVDs.
Any emitter is a target. Remember the old smokers' saw from the Boer War: Third man on a match is the dead man (1st Face = locate, 2nd Face = aim, 3rd Face = splatter).
[This message has been edited by Mykl (edited 12-05-98).]