I went out and bought the above colorometer, only to find out when I got back that it isn't recommended for Linux. I live in Thailand, and returns are not that easy. The installation CD has a defect, so I could always try... I have seen that profiling and calibrating should be possible in linux. I'm doing it right now. I'm just wondering about the 'pro' bit of my expensive new purchase. This means that the device is able to measure ambient lighting. On this page (http://www.argyllcms.com/doc/instruments.html#spyd3) it says "The ambient light sensor can be used with the Spyder3Elite and Spyder3Pro instruments, but returns a monochrome reading" Does this mean that the ambient light sensor is useless to me? I am a complete beginner to this field; sorry if my question is ignorant. I only use my monitor in three conditions. 1) dark 2) fluorescent lighting 3) indirect sunlight If I cannot go any further with the ambient light sensor in linux, is there a way I can use it to measure the three lighting situations I've given in Windows, and then to save three separate profiles to be used under linux? Many thanks, Kit