Testing a computational model of light-adaptation dynamics.

T E von Wiegand; D C Hood; N Graham

doi:10.1016/0042-6989(95)00047-4

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Testing a computational model of light-adaptation dynamics.

T E von Wiegand·D C Hood·N Graham

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Abstract

Experiments from the periodic and aperiodic traditions were used to guide the development of a quantitatively valid model of light adaptation dynamics. Temporal contrast sensitivity data were collected over a range of 3 log units of mean luminance for sinusoids of 2 to 50 Hz. Probe thresholds on flashed backgrounds were collected over a range of stimulus-onset asynchronies and background intensities from 0.1 to 1000 td. All experiments were performed foveally in the photopic range and used a consistent stimulus paradigm and psychophysical method. The resulting model represents a merging of elements from both traditions, and consists of a frequency-dependent front-end followed by a subtractive process and static nonlinearity.

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Adaptation, Ocular Adult Contrast Sensitivity Flicker Fusion Humans Light Mathematics Models, Biological Psychophysics Sensory Thresholds Spectrophotometry Time Factors Journal Article Research Support, U.S. Gov't, P.H.S.

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T E von Wiegand, D C Hood, N Graham. 1995. Testing a computational model of light-adaptation dynamics.. https://doi.org/10.1016/0042-6989(95)00047-4

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