Illuminating Engineering Society, Association of Public Lighting Engineers (Great Britain) · [London] · leaf 153
Fig. 25.—Larger view of shadows cast b^-single direct unit in centre of room … Fig. 2G.—Larger view of shadows cast bysingle indirect unit in centre of room. object is usually illuminated partly bydirect light from the sky and partlyby reflected light from the walls andground, sometimes receiving the majorportion of its illumination from theskj^, and sometimes vice versa,…
Lighting
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