Jim Worthey,
                        Lighting and Color Research
home page contact about me
Jim Worthey • Lighting & Color Research • jim@jimworthey.com • 301-977-3551 • 11 Rye Court, Gaithersburg, MD 20878-1901, USA

Vectorial Color
At Color Imaging Conference 16
Portland, Oregon
Tuesday, 2008 November 11, 1:30 - 3:30 pm
Instructor will be Jim Worthey

The 2007 tutorial (CIC 15) occurred with 10 Students, who kindly posed for a class picture. Below the picture is information for 2008.
Class picture
For the full jpeg from the camera, right-click this link and save it.

Course Description: When the right color matching functions (CMFs) are used, vector methods demystify camera sensors, lighting, and other topics. In Jozef Cohen’s invariant formulation, the vectors of spectral lights at unit power define the “locus of unit monochromats” (LUM). Orthonormal opponent CMFs map lights into Cohen’s color space and establish intuitive axes: whiteness, red-green, and blue-yellow. If a camera’s LUM matches the eye’s, it meets Luther’s criterion. The instructor presented details at CIC12 and CIC 14. The course emphasizes the practical use of color vectors and the orthonormal CMFs. If you plan to bring a computer to the course, please install a VRML viewer prior to attending. For background, see below.

Benefits: This course will enable the attendee to

  • Use the orthonormal CMFs, and calculate color vectors.
  • Understand the Locus of Unit Monochromats and the role of vector amplitude.
  • Work with 3D plots of such data as color chips under a lighting change.
  • Compare light sources on the basis of vectorial composition.
  • Generate a camera’s orthonormal basis, and compare it to the eye’s. The algorithm is simple, then understanding may take a little time.

Intended audience: Scientists and engineers who design or apply camera systems or lights. While certain applications will be stressed, the vectorial approach applies to all color work. For example, multi-primary systems and image compression are natural applications.

James Worthey received a BS in EE and an MS in Physics, then a PhD in Physiological Optics from Indiana University. He researched lighting and color at the National Institute of Standards and Technology, and published several applications of opponent colors. A breakthrough came in 2003 when he combined opponent colors with Cohen’s ideas and computer graphics.

Background Information
VRML viewer: If you are considering the tutorial, or just want to browse this web site, it will be helpful to install the Cortona VRML Viewer, so you can view the 3-dimensional graphs:
Reading materials:
¡See you in Portland! (The 2008 Portland meeting is past. But the short course can be done with a small or large audience almost anyplace.)

Jim Worthey Home Page: http://www.jimworthey.com
Copyright © 2007 James A. Worthey, email: jim@jimworthey.com
Page last modified, 2014 June 12, 16:00