I'm interesting in entering the world of color management and I'd like to calibrate the monitors on my home computer, but it's not clear whether or not the less expensive color calibration devices will adjust more than one monitor. I'm currently using an iMac Core2Duo with the display spanned to an additional 2007wfp (Dell monitor). Will I need to buy a special color calibrator to adjust both the built-in monitor and the external monitor? I'm specifically interested in the Huey because of its low price. Thanks!