IsoTesters have, by design, internally used raw readings of CIE Lab, determined from digital scanner RGB color measurements, from the very beginnings in the late 1990s. Simplistically, raw CIE L readings are forced to track AMS Rd and, similarly, raw CIE b is forced to track AMS +b. (Raw CIE a readings are internally available.) These automatically produced calibrations will be shown to excellent and remarkably stable.

Significant interest has been expressed in the past couple of years in moving to cotton color measurements which may be traced to other instruments than the Master Colorimeter in Memphis. Frequently mentioned are methods enabling tracability to the US National Institute of Standards and Testing. Further, interests have been expressed in moving from the historically older Rd & +b, 2 coordinates, to more modern and more widely used CIE Lab, and to all 3 color coordinates.

We note with emphasis that these interests were anticipated in the IsoTester design.

These interests may, hopefully for our industry, turn into actions. If so, there are optimum action paths to realizing both objectives of traceability and CIE Lab data products. There are also non-optimum paths.

It is the senior author's unabashed purpose to point the way to the right path and the consequences of taking the wrong path.