Motion picture electricity (1914) (14597409329)

Identifier: motionpictureele00hall (find matches)

Title: Motion picture electricity

Year: 1914 (1910s)

Authors: Hallberg, Josef Henrik, 1874-

Subjects: Motion picture theaters Electric lighting

Publisher: New York city, The Moving picture world

Contributing Library: The Library of Congress

Digitizing Sponsor: The Library of Congress

Text Appearing Before Image:

illu-mination in the direction of the condensing lenses, but thenet result is practically no better than from carbon set-tings illustrated in Figs. 100 and 103. This statement may seem unreasonable to many, butwhen the reader takes into account the point that the con-densing lenses of a projector arc lamp bring into focuson the spot at the aperture plate an exact imageof the craters, it is easy to understand that therewill be a very brilliant spot on the upper part of theaperture from the lower crater and another brilliantspot on the lower part of the aperture from the uppercrater, but right in the center there will be a purple orviolet streak which represents the arc which is not backedup by a crater, but which is in front of the air space be-tween the rear part of the upper and lower craters. Having mastered the foregoing argument, you willreadily understand that in order to focus both craters inFigs. 105 and 106 it would be necessary to bring the rear 182 MOTION PICTURE ELECTRICITY

Text Appearing After Image:

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electric lighting motion picture electricity 1914 book illustrations images from internet archive library of congress

1914

Library of Congress

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public domain