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Colour Under Some New Fluorescent Lamps

Garry Thomson
Technical Bulletin Volume 9, 1985


Artificial lighting of museums and galleries is now largely done by fluorescent tubes. Many have good colour-rendering properties, and are cheaper to run than tungsten filament lamps. But although newer fluorescent tubes of recent introduction (triphosphors) have an even higher efficacy (light in lumens per unit quantity, or watt, of electricity), their colour rendering is poor.

The article explains the basic requirements, colour discrimination, metamerism, colour temperature and the two systems of calculating colour rendering (CIE color shift; Crawford/NPL spectral band). Unfortunately lamps with best colour rendering have not sold well, and Philips 37 and 27 have been withdrawn. Economic pressures make museums want high efficacy, but until recently this meant poor colour. Now, however, lamps which perform well from both points of view are available; their properties are tabulated, and recommendations given for museum and gallery basic requirements.


colour, cost control, fluorescence, lamps, lighting, metamerism, museums, requirements

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Colour Under Some New Fluorescent Lamps, Garry Thomson (PDF 3MB)

To cite this article we suggest using

Thomson, G. 'Colour Under Some New Fluorescent Lamps'. National Gallery Technical Bulletin Vol 9, pp 5–11.

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