Movie Makers (Jan-Dec 1942)

MOVIE MAKERS 343 MOON'S ECLIPSE AUGUST 25th PETER A. LEAVENS, ACL ON TUESDAY night. August 25, our summer full moon will pass through the shadow cast into space by the earth, causing a total lunar eclipse. This event is to be visible from most of North America, and it will therefore provide a fine opportunity for movie makers who are interested in astronomical events. The circumstances of the August 25 to 26 eclipse are as follows. The moon enters the shadow proper, or umbra, at 10:00 P. M. The total phase begins at 11:01 and ends at 12:35 A. M. These are the hours of Eastern War Time, and time should be deducted as usual for other zones. Luna leaves the main shadow at 1:35 A. M. Prior to its entry and after clearing it, the moon passes through the penumbra, at which time an imaginary observer on the moon would see the earth partially eclipsing the sun. During the long totality period, the moon will glow with a faint coppery tinge. As to equipment, telephoto lenses are of course imperative, to give a satisfactory image of the moon. For scenes including some terrestrial objects, a four inch focus is adequate with 16mm. However, since in August we shall concentrate on the moon alone, a longer focus objective is recommended. The six inch lens, generally available and owned by many movie makers, meets this criterion. Because of the very weak light emitted by the moon when it is nearly all immersed in the earth's shadow, only the more brilliant phases of the eclipse can be captured on Kodachrome; but fast black and white emulsions will permit covering virtually the whole phenomenon. So that the finished film will show actual eclipse motion, it is wise to use the single frame device if your camera is equipped with one. If you do not have a single frame device, use the slowest running speed, if only to gain exposure time. In stop motion, the shutter should be tripped once or twice a second; count the frames so that sufficient screen time will result, depending upon whether the picture is for projection at silent or sound speed. You need not be told that your camera must rest on an extremely heavy and secure stand of some sort, both to permit single frame exposures and to avoid general vibration which a telescopic lens would exaggerate. Following is a basic guide, rated for Kodachrome. with absolutely clear skies at sea level. Proportional corrections, depending upon the local weather, can be made by the individual. Correct exposure will plainly reveal markings on the moon. When using stop motion, it is very important to test "drift," or passage across the field, caused by rotation of our world. Then, place the camera in relation to the moon at the beginning of the scene, so that the moon will ride over the picture center during a "take." 9:55 P. M. (Here the moon is deep in the penumbra; although the naked eye will fail to detect anything outstanding, by all means, make a continuous scene of the moon with color film. The actual darkening of one limb of the moon, together with penumbra shades, is astonishing when seen on the screen.) Take at least a twenty second run at //5.6. 10:15 P.M. (Now the shadow will take a large "bite" out of the moon.) Use stop motion over several hundred frames, at an aperture of //4 (//4.5 will suffice). 10:30 P. M. (The moon is half eclipsed.) Employ stop motion, at f/2.8. Further phases are too faint for Kodachrome except when the shutter speed is • Top, frame enlargement of a partial eclipse of the moon and, below, the author's camera with telephoto lenses, ready for eclipse filming. tke Wovie WaLr and the r\eCaiier : 60ERZ PHOTO LENSES are an AMERICAN product since 1899 made by AMERICAN labor in an AMERICAN-owned factory We have NO CONNECTION with any other firm TO THE RETAILER Because of their accuracy Goerz lenses are front line photo-optical equipment in many fields of activity of our Nation at War. The utmost is being done to meet the demands of the Government for these photographic precision tools. From time to time there may be available some of these fine anastigmats for civilia7i use and so we invite you to write us about your requirements. There is a Goerz Lens for every purpose. To help you in the selection of the proper lens our long experience is at your service For detailed information and prevailing prices see your dealer or address DEPT. MM-8 C. P. GOERZ AMERICAN OPTICAL CO. Office and Factory ir 317 East 34th Street New York * 8 ENLARGED «g ^* REDUCED A to IDtoO Black and White or Kodachrome GEO. W. COLBURN LABORATORY Special Motion Picture Printing II97-M MERCHANDISE MART CHICAGO RECORDS MOOD MUSIC and SOUND BACKGROUNDS The last word in sound effects Send for free catalogue THOMAS J. VALENTINO, Inc. Depf. MM 1 600 Broadway New York, N. Y.