Illuminating Engineering Society, Association of Public Lighting Engineers (Great Britain) · [London] · leaf 58
hen they had been obtained theycould only act as a guide to the desiredresult. It was difficult to predict thevisual result due to a variation of sucha curve. After using a spectrophoto-meter he had found it necessary to makedirect comparisons between the appear-ance of any given pigment under… … A specimen of painted or dyedmaterial A B is half covered by a box containing a lamp and open at the bottom.The material is observed from thedirection 0, half of it being illuminatedby daylight and half by artificial light.The position of the lamp can be alteredto control the brightness of the…
Lighting
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