linux. I'm doing it right now. I'm just wondering about the 'pro' bit of my expensive new purchase.
Hi, the "Pro" bit means that you've bought more expensive MSWin/OS X software with the instrument.
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?
If you're after some sort of fancy/funny "automatic dynamic display adjustment based on current ambient light", then yes, since (AFAIK) there is no support for this "feature" on Linux. Personally, I think that such a feature is incompatible with serious color, and a better approach is to control the monitor viewing environment if color is important. If you want to use the ambient measurement to allow for some of the viewing environment conditions, (ie. dispcal -a parameter), then you can certainly do so, as a color reading isn't needed.
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?
You can create calibration curves and ICC profiles with perceptual tables that make some allowance for viewing conditions in Argyll. For calibration, see <http://www.argyllcms.com/doc/dispcal.html#a> and for ICC profiles see <http://www.argyllcms.com/doc/colprof.html#d> Graeme Gill.