Approximate field measurement of surface luminance using a digital camera

Abstract

This paper describes a method of estimating and recording surface luminance using widely available types of digital cameras and photographic image processing software. The method involves recording the luminance of a 10-step grey scale placed within a scene at the time an image is captured. The relationship between luminosity (a value obtainable from the software) and luminance of the grey scale may then be used to determine the luminance of surfaces within the scene to an accuracy of within 10%. The technique has been successfully applied to interior and exterior scenes lit in a variety of ways and to a number of types of digital camera. The methodology, robustness and limitations of the technique are set out.

Get full access to this article

View all access options for this article.

References

Slater A.I. , Carter D.J. and Moore T.

A study of lighting in offices equipped with occupant controlled systems

Proceedings of the First CIE Symposium on Lighting Quality

Ottawa, Canada (Vienna : CIE ) pp 219-227 (1998)

Loe DL , Mansfield K.P. and Rowlands E.

Light patterns and their relevance to spatial appearance and the quality of the lit environment

Proceedings of the 22nd Session of the CIE, Melbourne, Australia ( Vienna: CIE) vol. 2 pp 41-44 (1991)

Flynn J.E. and Spencer T.

J A study of subjective responses to low energy and non-uniform lighting systems

Lighting Design and Application 7(2)6-15(1977)

Rowlands E. , Loe D.L. and Brickman N.T.

Instrumentation for measuring the luminance distribution within the visual field

Proceedings of the CIBSE National Lighting Conference, Cambridge ( London: CIBSE) pp 187-192 (1986)

Weaver N.L. , Robbins C.L. , Hunter K.C. and Cannon T.W.

Development of a second-generation, video-based luminance mapper of daylighting research

Proceedings of the 1986 International Daylighting Conference, Long Beach vol.2, pp 199-209 (1986)

Rea M.S. and Jeffrey I.

G A new luminance and image analysis system for lighting and vision—I. Equipment and calibration

J. Illum. Eng. Soc. 19(1) 64-72 (1990)

Berrutto V. and Fontoynont M.

Applications of CCD cameras to lighting research: review and extension to the measurement of glare indices

Proc. CIE 23rd Session, New Delhi CIE Publication 119 vol.1 pp192-195 (1995)

BerruttoV. Métrologie de la qualité visuelle des ambiances lumineuses: application à l'éclairage des bureaux PhD thesis, University of Savoie Chambéry pp 145-185 (1996)

Hayman S. , Roy G. and Julian W.

The use of the Nikon/Fuji digital camera for cloud detection and sky luminance evaluation

Proc. CIE 24th Session, Warsaw CIE Publication 133 vol.1 part 2 pp 148-150 (1999) 11 Nemeskeri R.L. Illumination ergonomics in computerized offices Masters thesis, University of Calgary pp 61-62 (1994)