Danny Rich

• B.S., M.S. in Physics, Ph.D. in Color Science
• Senior Color Physicist at Sun Chemical

A study of the agreement between a visual assessment and the measurement of the reflectivity of printed metallic inks was performed. A psychophysical property for this percept was identified as visual brilliance. The visual judgments of a series of printed panels were compared with measurements from various types of specular reflectance instruments...

Solid-state lighting in the form of light emitting diode lamps is quickly taking over the world as replacements for existing lower efficiency lamps. The lighting standards, which phased in from 2012 to 2014, do not ban incandescent or any specific lamp type, but they do require that lamps need to use about 25% less energy. The bipartisan Energy Ind...

This communication contains Rich's Letter to the Editor commenting on a recent article by Roy S. Berns, and Bern's Reply to the Letter. The letter introduces more information on the concepts of Depth and Brightness as well as references. © 2014 Wiley Periodicals, Inc. Col Res Appl, 2014

A visible-attenuated total reflection (visible-ATR) device was designed to provide a method for directly determining the relative tint strength in high-strength inks. This device showed good reproducibility and the spectra could be correlated to known values of relative tint strength in viscous, highly pigmented inks well within the industry-accept...

A recent ASTM specification (ASTM E2214-02) was created to standardize the terminology and procedures used to evaluate color measuring instruments. This specification addresses the need for uniformity among the manufacturers of such instruments when quantifying the performance of their products. The scope of E2214 is necessarily large, covering the...

Part I described an experiment in which the repeatability of a number of common, commercially available spectrocolorimeters was compared using ASTM procedures. ASTM E2214-02 Standard Practice for Specifying and Verifying the Performance of Color-Measuring Instruments is intended to standardize the terminology and procedures used to evaluate color m...

Moderate (0.5–1.5 CIELAB units) color differences in surface colors were scaled visually to obtain color-dif-ference-perceptibility ellipses. The ellipse orientations appeared to be independent of the size of the color differences over the range indicated, and were consistent with literature results obtained with visual colorimeters. In the uivid g...

IntroductionColorimetryVisual ColorimetryColorimetry by Analog Simulation of Visual ColorimeterColorimetry by Digital Simulation of a Visual ColorimeterSpectrocolorimetryExtension of Basic Colorimetry to Prediction of Color DifferencesConclusions and Recommendations

CORM Technical Subcommittee OP-1 under Optical Properties of Materials, has undertaken a round-robin inter-comparison of several industrial laboratories. The basis of the inter-comparison is similar to that reported by Verrill and by Rich in that the Ceramic Colour Standards were shipped from one laboratory to the next. There were six participants...

This is a textbook at the entry level on the industrial technology of colorimetry. This paper is a review of that textbook. The copyright is owned by John Wiley & Sons and reprints are only available through the publishers.

A proposal by Robertson slightly modified by Berns and Petersen, to use spectral differences to predict systematic errors in spectrophotometers has found limited success in practical application. Porter suggested a way to improve the level of agreement between standardizing laboratories based on the Berns and Petersen method but suggested using der...

There are many parameters that contribute to the quality of the measurement of the diffuse spectral reflectance factor of colored materials. This paper focuses on the challenges associated with the evaluation of the long term repeatability of the diffuse / near-normal, reflectance spectrophotometic instrument. At the 1992 AIC Interim Meeting at Pri...

This article addresses the results of the recent North and Fairchild article on observer metamerism. It reports on the results of a different experiment that produced similar results to those of North and Fairchild. The history of observer metamerism is outlined briefly and some possible sources of the large variations in inter-observer matches are...

The task of instrumental measurement of the color of nonimpacting printing is addressed. The majority of the instrument and sample parameters that can introduce systematic errors in the instrumental readings are identified. For selected cases, proper measurement procedures are identified. In other cases, the user is warned of the problem and must d...

A high performance, miniature, dual-channel spectrometer has been design ed for use in spectrocolorimeters. It contains an aberration corrected holographic grating at f/1.6 and two custom photodiode linear arrays (128 channels each) covering the visible spectrum (380 nm to 720 nm). The spectrometer is interfaced with optical fibers and is calibrate...

We describe an experiment to visually quantify the accuracy of the simulation of the color and color-difference of surface samples on a CRT display unit. A gray-scale-anchored, magnitude-estimation experiment was performed to assess the absolute quality of the simulations and a forced-choice, paired-comparisons experiment was performed to assess th...

In a previous article [R. Stanziola, B. Momiroff, H. Hemmendinger, Color Res. Appl. 4, 157–163 (1979)], a new generation of scanning spectrophotometer was described. The new generation instrument contained many improvements to the recording spectrophotometer designed by A. C. Hardy. This article describes the progeny of that generation. Continued i...

A daylight simulator for an integrating sphere reflectometer is assessed, both in the visible and the UV regions of the spectrum, to determine the goodness of fit to CIE Standard Illuminant D65. The feasibility of optimizing the daylight source to adhere closely to CIE Standard Illuminant D65 by operator accessible means is demonstrated. Data are p...

The debate over the best optical geometry for color measurement dates back to the development of the first recording reflectance spectrophotometer. It is hypothesized that a bidirectional geometry conforms best to the procedure used to inspect colored surface samples visually. This hypothesis was tested using two spectrophotometers of nearly identi...

A technique for direct determination of the parameters of color difference perceptibility ellipses for supra-threshold surface color differences was developed. Two surface color centers were selected. One was a vivid greenish yellow painted paper and the other was a deep greenish blue painted paper. Three color difference levels were developed at a...

A Euclidean metric for colorimetric evaluations based on an opponent-color system was described by Ingling and Tsou. The metric was shown to work well for predicting the results of the standard color-discrimination experiment. The metric is applied to the surface-color data of the Munsell collection, the Morley, Munn, and Billmeyer data, and the da...

Recent advances in optical and electronics technology have given rise to a new generation of color-measurement instrumentation. The most frequently observed instrument is the microcomputer-controlled spectrophotometer. The new computer-controlled instruments exhibit unparalleled speed and precision. The speed allows one to make multiple measurement...

A new generation of color-measuring instruments now available features unconventional approaches as well as advances in conventional optics and electronics. Most of the new instruments are interfaced to computers or include microprocessors which allow measurements to be made in seconds, followed immediately by a wide variety of calculations. The tr...

A whole new generation of color-measuring instruments now available features unconventional approaches as well as advances in conventional optics and electronics. Almost all the new instruments are interfaced to computers or include microprocessors which allow measurements to be made in seconds and followed immediately by a wide variety of calculat...