Negative lights are what they suggest - 'lights' which actually remove light from an area, a la black holes. If you were to light an area with infint light, for example, then place a negative spot within the scene, then there would be a lovely splat of darkness in your otherwise illuminated scene. So this isn't the way to go, I think... Regarding using lights. I did a little test file up in Photoshop, using the basic three circles of primary colour and desaturating the thing afterwards, to find out the relative luminosities of different coloured light. Would this b of help to anyone who wants to give their images the look that they've been coloured, without actually using colour in the lights (if that makes sense?) jonthecelt (formerly friendlyrogue)