The graphs below use the shortest form of the Color Accuracy test from Spyder4Elite’s Advanced Analysis Suite (other versions measure 24 or 48 patches, instead of 12). The top graph shows the accuracy of colors displayed using sRGB as the display profile, a fairly common default setting. The sRGB error values are as high as 4.42 Delta-E, with an average of 2.54, and a least error of .98, which is about 1.00 Delta-E, meaning barely visible to the human eye under appropriate conditions. So it would be safe to say that virtually all the colors in this test would present visible variation from the desired color, when using the display in this manner.
The next graph shows the same display calibrated with Spyder4Elite, and with that calibration and custom profile in place when the test was run. Here the maximum error is reduced from 4.42 to 2.97, the average is reduced from 2.54 to 1.14, and the minimum error is reduced from .98 to an amazing .19, or a fifth of what the human eye can typically detect. Here the average deviation from the intended colors is at the “barely visible” level.
Two of those colors are out of range for a reason. The black of the Cinema Display is not as dark as the black in the SpyderCheckr black patch; and it produces the same gamut limit value in both cases, within 2/100 of a Delta-E, showing excellent consistency on the part of the Spyder4. And the Cyan Patch from the Datacolor SpyderCheckr (the source of the Lab colors used in this test) is slightly outside the gamut of sRGB, and of standard gamut displays. Here, despite the gamut limit issue, the calibrated result reduced the patch error from 4.42, to 2.76. In fact, every sample except for the consistent black, had a reduction in error though display calibration and profiling.
Calibration of a high end graphics monitor typically results in Delta-E values of about half what occurs on Apple displays, so a further reduction in error could be achieved with an Eizo, NEC, Quato, or other high end display model. Such displays are typically wide gamut as well, eliminating the Cyan error shown here. And they offer increased display uniformity. My next article on this topic will compare a general purpose display to a high end graphics display in terms of Uniformity.