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.
March, 1931
AMERICAN C I N E M A TOG R A P H E R
Thirty-five
Screen Definition
(Continued from Page 15)
Moore filter No. 1 (No. 64 and 27) is recommended when as an example a sunset over water is photographed, reducing sun to a definite disc, but maintaining characteristic details and contrasts on water reflections.
This is the densest combination filter of the series of six published in a previous issue.
i «■ * o I
f;#. 6
^HMH ■!*.
Fig. 4
Fig. 5
It is unfortunate that the selection of proper filters or filter combinations for especially desired effects is in each instance a delicate problem, the solution of which so greatly influences final screen definition.
The great number of conditions, above cited, call for careful consideration of their relative values and no set rule can be given for correct filter use.
The chart Fig. 1 , however, offers certain assistance for these problems and has been found of reliable value.
It is, however, of prime importance to always keep in mind that any filter — 1, invariably reduces lens speed and 2, that it increases the actinic reaction for its complementary color value but only relative and never absolute.
In the next article a complete list of 20 Moore filters with their approximate multiplication factors and their individual characteristics will be published as a valuable guide for filter work.
Amateur Movie Making
(Continued from Page 30)
"filter factor" is 1.5. That js, when using a K 1, the normal exposure must be multiplied by 1.5. With the K IV2, the factor is 2; and with the K 2, it is 3. Therefore, in practical use, with a K 1 the diaphragm opening should be increased half a stop; with a K 1 V2, a full stop; and with a K 2, a stop and a half. In other words, if a scene required f:8 as a normal, unfiltered exposure, it would require f:6.3 if a K 1 filter were used, f:5.6 with a K 1 V2, and f:4.5 with a K 2; all of which is a powerful argument in favor of the use of largeaperture lenses.
nr 7
e 8 S 3 8
F,>6
Fiq,l
Fif. II
Ftp.lZ
"l,™«"^B I^M HIMWBBHlBWIiiif '
A