Journal of the Society of Motion Picture Engineers (1930-1949)

Record Details:

Title:
Journal of the Society of Motion Picture Engineers
Date:
1930-1949
Publisher:
New York, N.Y. : The Society
Volume:
Journal of the Society of Motion Picture Engineers
Leaf #:
000558
Language:
English
Collection:
Technical Journals
Format:
Periodicals
Contributor:
Prelinger Library
Sponsor:
MSN
Coordinator:
Media History Digital Library
Description:
The Journal of the Society of Motion Picture Engineers (SMPE)Êdocuments the technological progress of the film industry, highlighting technical developments in production and exhibition. Of special interest are articles about special effects, theater practices, lighting, and the introduction of the 16mm format. Initially titled "Transactions of the Journal of the Society of Motion Picture Engineers."Digitized by the Prelinger Library and the Library of Congress Motion Picture, Broadcasting and Recorded Sound Division.
Date Added:
July 19, 2022
Something wrong or inaccurate about this page? Let us Know!

Thanks for helping us continually improve the quality of the Lantern search engine for all of our users! We have millions of scanned pages, so user reports are incredibly helpful for us to identify places where we can improve and update the metadata.

Please describe the issue below, and click "Submit" to send your comments to our team! If you'd prefer, you can also send us an email to mhdl@commarts.wisc.edu with your comments.




We use Optical Character Recognition (OCR) during our scanning and processing workflow to make the content of each page searchable. You can view the automatically generated text below as well as copy and paste individual pieces of text to quote in your own work.

Text recognition is never 100% accurate. Many parts of the scanned page may not be reflected in the OCR text output, including: images, page layout, certain fonts or handwriting.

1949 CATHODE-RAY OSCILLOGRAPHY 555 the trace varies with the exposure because of the nonunif orm light distribution across the trace. One may therefore, obtain any fineness of line required, within limits, by a choice of the proper exposure. In general, the exposure should be such as to include a sufficient number of cycles of this repeating phenomenon so that no part of the sweep is lost. If the exposure is shorter than this, there will be a visible interruption at the time of shutter opening or closing. This is not usually of importance except at very low speeds, because at high speeds one (a) (b) Fig. 7 — (a) Partial loss of recording caused by improper length blanking gate; (b) proper blanking gate. (a) (b) (c) Fig. 8 — Effect of exposure time on a varying phenomenon: (a) too short; (b) correct; (c) too long. cannot open and close the shutter rapidly enough to include less than one sweep. Where the phenomenon is not reproducible, and it is desired to include only one cycle, one may use electronic control of the exposure by means of a gating pulse applied to brighten the beam. It is desirable to have the length of the gate as close to one cycle as possible. Fig. 7 shows a typical polar co-ordinate recording of a vibration in connection with a rotating machine in which the gate in the first oscillogram is of proper duration, and in the recording next to it, is so