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C H Elzinga

Publications and source records attributed to C H Elzinga.

4 recordsLinked to original sources

Spectral sensitivity functions derived from brightness matching: implication of intensity invariance for color-vision models.

It is demonstrated that brightness sensitivity functions are self-similar; i.e., unique up to multiplication by a positive constant. This invariance leads to a structural restriction for sensitivity models that are formulated in terms of action spectra of cone systems. The heuristic value of this restriction is demonstrated through simulations on various kinds of data on direct brightness matching and brightness magnitude estimation on the basis of a new model for brightness sensitivity that accounts for both superadditivity and subadditivity.

Color Perception↗

Nonlinear codes for the yellow/blue mechanism.

The opponent yellow/blue mechanism is studied by means of an iso-cancellation technique. A qualitative and quantitative analysis of different photopigment models for the yellow/blue code is presented. On the basis of this analysis we provide a new model which ascribes the nonlinear character of the code to a power transformation of the short wave cone activity. This new model leads to predictions concerning the wavelength shift of the short wave component of a unique red. Tests of these predictions support the new model.

Color Perception↗