July 2019
Volume 19, Issue 8
Open Access
OSA Fall Vision Meeting Abstract  |   July 2019
A chromaticity diagram in which real-world colors lie outside the spectrum locus
Author Affiliations
  • J. D. Mollon
    Department of Psychology, University of Cambridge
  • P. Chaudhuri-Vayalambrone
    Department of Psychology, University of Cambridge
  • P. B. M. Thomas
    Department of Paediatric Ophthalmology and Strabismus, Moorfields Eye Hospital, London
Journal of Vision July 2019, Vol.19, 107. doi:https://doi.org/10.1167/19.8.107
  • Views
  • Share
  • Tools
    • Alerts
      ×
      This feature is available to authenticated users only.
      Sign In or Create an Account ×
    • Get Citation

      J. D. Mollon, P. Chaudhuri-Vayalambrone, P. B. M. Thomas; A chromaticity diagram in which real-world colors lie outside the spectrum locus. Journal of Vision 2019;19(8):107. https://doi.org/10.1167/19.8.107.

      Download citation file:


      © ARVO (1962-2015); The Authors (2016-present)

      ×
  • Supplements
Abstract

One of the several attractive features of the MacLeod-Boynton chromaticity diagram is that generic forms of the diagram can readily be constructed for observers other than the standard Judd(1951) 2-degree observer. Thus, for example, MacLeod-Boynton diagrams can be created for a large-field observer or for a particular type of anomalous trichromat or for a catarrhine or platyrrhine primate. When we constructed a generic MacLeod-Boynton diagram for one human trichromatic phenotype that has been reported in the literature, a very curious feature emerged: The gamut is not delimited by the spectrum locus. The chromaticities of foliage lie firmly outside the spectrum locus. Some real-world stimuli have excitation purities >100% and others have negative purities. To model the cone sensitivities of the phenotype we used Trevor Lamb’s template and assumed standard values for the density of the lens and of the macular pigment. To model the chromaticities of real-world stimuli, we took reflection spectra from the Cambridge Database of Natural Spectra and multiplied them by the power spectra of natural daylight illuminants. The remarkable characteristics of this generic MacLeod-Boynton diagram may prove useful in detecting observers who exhibit the phenotype in question.

×
×

This PDF is available to Subscribers Only

Sign in or purchase a subscription to access this content. ×

You must be signed into an individual account to use this feature.

×