This historic book may have numerous typos and missing text. Purchasers can download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1921 Excerpt: ...surface radiating or reflecting one lumen per cm2. Equivalent to a perfectly diffusing surface with illumination of one phot. A perfectly diffusing surface emitting one lumen per ft2 has a brightness of 1.076 millilamberts. Brightness in candles per cm2 is reduced to lamberts by multiplying by v. A uniform point source ...
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This historic book may have numerous typos and missing text. Purchasers can download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1921 Excerpt: ...surface radiating or reflecting one lumen per cm2. Equivalent to a perfectly diffusing surface with illumination of one phot. A perfectly diffusing surface emitting one lumen per ft2 has a brightness of 1.076 millilamberts. Brightness in candles per cm2 is reduced to lamberts by multiplying by v. A uniform point source of one candle emits 4/r lumens. One lumen is emitted by.07958 spherical candle power. One lumen emitted per ft2--1.076 millilamberts (perfect diffusion). One spherical candle power emits 12.57 lumens. One lux-i lumen incident per m2 =.0001 phot =.1 milliphot. One phot-i lumen incident per cm2-10,000 lux-1000 milliphots. One milliphot-.001 phot-.929 foot-candle. One foot-candle = i lumen incident per ft1-1.076 milliphots-10.76 lux. One lambert = i lumen emitted per cm2 of a perfectly diffusing surface. One millilambert =.929 lumen emitted per ft2 (perfect diffusion). One lambert =.3183 candle per cm2 = 2.054 candles per in2. One candle per cm2--3.1416 lamberts. One candle per in2-.4968 lambert-486.8 millilamberts. Adapted from 1916 Report of Committee on Nomenclature and Standards of Illuminating Engineering Society. See Tr., Vol. n, 1916. Smithsonian Table. TABLE 300.--Photometric Standards. No primary photometric standard has beer, generally adopted by the various governments. In Germany the Heiner lamp is most used; in England the Pentane lamp and sperm candles are used; in France the Carcel lamp is preferred; in America the Pentane and Hefner lamps are used to some extent, but candles are more largely employed in gas photometry. For the photometry of electric lamps, and generally in accurate photometric work, electric lamps, standardized at a national standardizing institution, are commonly employed. The " International candle " ...
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Add this copy of Smithsonian Physical Tables to cart. $21.42, new condition, Sold by Ingram Customer Returns Center rated 5.0 out of 5 stars, ships from NV, USA, published 2022 by Legare Street Press.
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Add this copy of Smithsonian Physical Tables to cart. $27.06, new condition, Sold by Paperbackshop rated 4.0 out of 5 stars, ships from Bensenville, IL, UNITED STATES, published 2013 by Hardpress Publishing.
Add this copy of Smithsonian Physical Tables to cart. $30.56, new condition, Sold by Paperbackshop rated 4.0 out of 5 stars, ships from Bensenville, IL, UNITED STATES, published 2013 by Hardpress Publishing.
Add this copy of Smithsonian Physical Tables to cart. $31.73, new condition, Sold by Ingram Customer Returns Center rated 5.0 out of 5 stars, ships from NV, USA, published 2022 by Legare Street Press.
