unit color-difference figures derived from the proposed cie 1976 l*a*b* space: erratum
TRANSCRIPT
Unit color-difference figures derived from the proposed CIE 1976 L*a*b* space: erratum
Ruth M. Rich and Fred W. Billmeyer, Jr. Chemistry Department, Rensselaer Polytechnic Institute, Troy, New York 12181. Received 8 January 1975.
Kuehni1 has pointed out an error in our recent paper2
that exaggerates the apparent magnitude of asymmetry in the color-difference figures referred to. The final sentence ("The figure for color 19 . . . " ) in the paragraph beginning "The twenty-eight figures . . . " should be replaced with the following:
"Kuehni1 has shown that the asymmetries resulting from the nonlinearity are only 2% or less of the ellipse radii at the 1 unit color-difference distance but increases to 6-10% at the 10 unit color-difference distance. From a practical point of view such asymmetries can usually be neglected."
In Fig. 2, the dotted reference circle should in fact be closer to the solid figure labeled CIE 1976 a*b*, and the final sentence in the caption be deleted. The remainder of the paper is not affected by the plotting error.
We thank Rolf Kuehni for calling this error to our attention.
References 1. R. Kuehni, Verona Dyestuff Division, Mobay Chemical Corp.,
Union, N.J., private communication. 2. R. M. Rich and F. W. Billmeyer, Jr., Appl. Opt. 13, 2475 (1974).
1770 APPLIED OPTICS / Vol. 14, No. 8 / August 1975