AVS Forum Special Member
Join Date: May 2008
Location: San Francisco - East Bay area
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So you get an inexpensiv spectro and a moderate cost colorimeter, now you're at $1000 for calibration hardware.
I've heard the "stories" about the i1Pro several times and don't believe them because every time I measure one with my own freshly calibrated meter, they are "off" enough to be an issue. This has happened about 6 times over the years.
You cannot assume that simple characterzation of a "faded" colorimeter against a specto is going to produce accurate readings in the colorimeter. The aging process of the filters is a complex process and the filters not only change color, their linearity (bright to dark) an become non-linear. So if you measure a single point as a calibration reference, only that particular luminance level might be correct. To get away with making a "faded" colorimeter accurate (temporarily), you'd have to build a correction matrix that would require measuring white, red, green, and blue at 10%, 20%, 30%... 90%, & 100%. That will take a while with a meter as slow as the i1Pro and the calibration software would have to support that sort of matrix calibration rather than the much more basic characterization. The newest colorimeters that have the filters in a sealed chamber in an attempt to extend their useful life before the filters begin to change significantly, but they are pretty expensive for someone looking for entry-level calibration hardware/software combos.
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