I have a situation in which I own four high quality spectrophotometers.
Recently, I used each device to measure a particular paper-white.
Predictably, I received four different measurement results.
The deltaE between any two devices ranged from .47 to 1.73.
Unfortunately, I have no idea which of the four results is closest to the truth, and I do not know what the maximum difference between device results is reasonable.
Obviously, .47 is acceptable. And, we know from Steve’s last ColorNews article, that a deltaE < 1.0 could also be considered acceptable.
So, perhaps a deltaE => 1.0 should be considered suspect?
Finally, can anyone recommend a test kit containing calibrated materials that I can use to periodically check the accuracy of my spectrophotometers?
I’m experiencing the same problem… My Techkon SpectroDens produces results that are quite different from my EyeOne. When measuring a MediaWedge with the Techkon I get results that are different and even contradictory to my EyeOne. And not only the paperwhite, but also the mean dE, the primary colors and graybalance…
I’m aware that no measurement device is the same, but I was unpleasantly surprised when I discovered that my < 1 deltaE proofs were actually 1.8 deltaE according to my Techkon.