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Applied Optics

Applied Optics


  • Vol. 42, Iss. 3 — Jan. 20, 2003
  • pp: 458–464

Color and luminance asymmetries in the clear sky

Javier Hernández-Andrés, Raymond L. Lee, Jr., and Javier Romero  »View Author Affiliations

Applied Optics, Vol. 42, Issue 3, pp. 458-464 (2003)

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A long-standing assumption about the clear sky is that its colors and luminances are distributed symmetrically about the principal plane. As useful as this approximation is, our digital-image analyses show that clear-sky color and luminance routinely depart perceptibly from exact symmetry. These analyses reconfirm our earlier measurements with narrow field-of-view spectroradiometers [J. Opt. Soc. Am. A 18, 1325 (2001)], and they do so with much higher temporal and angular resolution across the entire sky dome.

© 2003 Optical Society of America

OCIS Codes
(010.1290) Atmospheric and oceanic optics : Atmospheric optics
(330.1710) Vision, color, and visual optics : Color, measurement
(330.1730) Vision, color, and visual optics : Colorimetry

Original Manuscript: January 8, 2002
Revised Manuscript: March 25, 2002
Published: January 20, 2003

Javier Hernández-Andrés, Raymond L. Lee, and Javier Romero, "Color and luminance asymmetries in the clear sky," Appl. Opt. 42, 458-464 (2003)

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