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Some new luminance-gradient effects.

D Zavagno
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Abstract

Three compelling luminance-gradient effects are described. The first effect concerns a brightness enhancement and a luminous mist spreading out from a central area having the same luminance as the white background and surrounded by four rectangular inducers shaded with a linear luminance gradient. The second effect is perceived with a photographically reversed configuration, and concerns what may be considered a brightness reduction or the enhancement of a darkness quality of a target area of the visual scene. The third effect concerns the perception of a self-luminous disk inside a somewhat foggy medium. The effects are worthy of further examination because they challenge current theories of luminosity perception and brightness perception in general.

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Contrast SensitivityForm PerceptionHumansOptical IllusionsPattern Recognition, VisualJournal Article

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BibTeXRIS

D Zavagno. 1999. Some new luminance-gradient effects.. https://doi.org/10.1068/p2633

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