Photometric linearity of optical properties instruments, Test Method TAPPI/ANSI T 1217 sp-23
This standard practice describes a test for linearity required by the following TAPPI optical methods:
T 425 Opacity
T 452, 525, 534, 646 Brightness
T 480, 653 Gloss
T 524, 527 Color
T 560, 562 Whiteness
This standard practice is normally used by instrument manufacturers as the procedure for correction of photometric linearity errors.