Human color vision depends on the relative activations of the long- (L), middle- (M) and short-wavelength (S) sensitive cone types, which vary in sensitivity across the visible spectrum. These spectral sensitivities, or cone fundamentals, are subject to individual differences caused by variability in (i) pre-retinal filtering by the lens and macular pigments that change the spectral power distribution of the light reaching the cones mainly at shorter wavelengths, (ii) photopigment optical density that changes the width of the spectral sensitivities; and, finally, (iii) in the genes that code the L and M-cone opsins that produce spectral shifts of their spectral sensitivities. Together these variations produce differences in our color vision - across the population, across the lifespan, and across the retina. They have significant implications for design, color reproduction, and display technologies.

In this webinar hosted by the Color Technical Group, Andy Rider will present a simple model to account for these differences based on the CIE 2006 standard and thus work by Stockman & Sharpe (2000) and recently extended by Stockman & Rider (2024) that allows the reconstruction of individual cone spectral sensitivities. The model is available as a Python program. Dr. Rider will also present some of his recent work in collaboration with Zhejiang University, applying the model to analyze new sets of color-matching data to estimate individual cone fundamentals and color-matching functions.

Subject Matter Level: Introductory - Assumes little previous knowledge of the topic

What You Will Learn:
• About individual variation in cone spectral sensitivities and a model to account for these
• Applying the new model to analyse colour matching data from individuals

Who Should Attend:
• Students, postdocs, and PIs interested in low level color vision
• Students, postdocs, and PIs with an interest in color reproduction on displays and individual differences between observers/observer

About the Presenter: Andy Rider from University College London

Dr. Andy Rider is a Senior Research Associate at the Institute of Ophthalmology, University College London. He has a BA in mathematics from the University of Oxford, Masters degrees in medical statistics and biological modelling, and a Ph.D in cognitive neuroscience from UCL. His research uses psychophysics and mathematical modelling to understand low-level processing in the human visual system, with specific application to colour vision, temporal sensitivity, and light adaptation. He has worked in Andrew Stockman’s Colour and Vision Research laboratory for over a decade.