Light, photometry and illumination : a thoroughly rev. ed. of ''Electrical illuminating engineering'' (1912)
Barrows, William Edward, 1878-1960 · New York ; London : McGraw-Hill Book Co. · leaf 115
luminosity curves showing thecomparison of the spectral colors with w^hite light. The appar-atus was so designed that it could be used for both the equalityof brightness and the flicker methods without disturbing any ofthe critical conditions. The tw^o illuminations used were 10 and 250 units,… … t -•« / \ .^f-. -^■^^ / \ \ P\ \\ // IJ V \ \\ \ V- \ ■7// \ ; \ \ \/ ,.. r ;\A v 1 . . H.E.L * » M.L. « F.E.C. H *■ C.f.U X < P.W.C. Mean Etiualitv of Brightness Method [UimunationioU Lmis \S\\ \\ i \ ■ \ f^ 0.50 fJ. 0.52 0.54 0.56 0.58 0.60 0.62 0.64 0.66 0.50 0.52 0.54 0.56 0.58 0.60 0.62…
Light · Photometry · Electric lighting
Internet Archive · Boston Public Library · Public Domain Mark 1.0. Free to use for anything.
![An illustration from Studies in the photometry of lights of different colours [electronic resource] / spectral luminosity curves obtained by the equality of brightness photometer and the flicker photometer under similar conditions (1912)](https://img.insideoutlibrary.com/img/200/ia-b21287569-75-0.webp)
