I have a set of L*a*b* measurements of color charts that I created with a i1Pro2 spectrophotometer. The Xrite software exports L*a*b* values on a scale of L*:0-100 and *a*b*: -100 to +100*. I've written a script for Photoshop to automate the calculation of specific metrics of captures of those charts, but there's one snag: Photoshop displays L*a*b* values on a scale of L*:0-100 and *a*b*: -128 to +127*. I assume, but I haven't been able to find confirmation, that it is a mathematically linear conversion (mapping) from the *-100 to +100 a*b* scale* to the *-128 to +127 a*b* scale.* Can anyone verify this? Or point me in the direction of the proper way to map the values between the two scales? Thanks, Mike -- *Mike Pucher* *Sr. Image Capture Specialist* *Animation Research Library* desk: 818.544.4185 (8223-4185)