[JimP]

A spectraradiometer, basically a device that will accurately measure the display and interpet the results scientifically.

Problem is that low cost solution don't work well with the ultra high pressure mercury bulbs that are typically used in LCD and DLP based projectors.

The professional devices run something in the range of $5K to $7K and require a periodic calibration. I've heard of calibrationist who didn't know that they had to have them calibrated, yet noticed that their calibrations always seemed a bit blue.

Another approach which is stupid simple is to use one of the $125 ish puck solutions to calibrate a CRT computer monitor. They are especially accurate on CRT displays. Display a split grayscale on your computer(jpeg file found on the internet) and a similar one through DVE onto your display(unless your willing to spend for the Accupel). Then its basically an exercise of making the two match. So for grayscale calibration, you are very likely to get a pretty good adjustment. One of the little known secrets is that the human eye is very sensitive to slight differences in color and more accurate at lower IREs than many of the devices that are marketed for display calibrations.