The international photographer (Jan-Dec 1934)

July, 1934 r i, INTERNATIONAL PHOTOGRAPHER Thirty-five distance from the lens, an "image" of the outer scene is formed thereon, by means of the "point to point" light pattern which is functioning there. The "pin-hole" camera varies this pattern of light play somewhat. The law of brightness plays only behind the lens, not before it. For example: The sun is about 400 times as far from the earth as the moon, yet in photographing them, the distances are irrelevent and only their respective brightnesses need be considered. The theoretical act of illuminating the molecule, in open nature, becomes practically, in photography, the illumination of the silver grains in the film, and what has transpired with the light on the opposite side of the lens is entirely irrelevent to the problem. Mercury is 41 of the sun's diameters distant from the sun. If we focus an image of the sun with stop F/41, that image will be as bright as the natural sunlight on Mercury. Another condition: If in some local spot on the earth a widespread cloud of even density throughout should be suspended, we could carry our grain of white chalk about both in the atmosphere below the cloud and in the cloud itself, without altering its intensity. I would like to hear from some ace who has risen with his plane through two or three miles of fog and come out into the sunlight above. I believe that the intensity within the mass is the same throughout, until arriving very close to the top of the bank. This is the law by which Vail explains the tropical conditions around the poles before the great vapor canopy descended to the earth. This mass carried its light and heat around the world and when the cooling earth reached the right condition, first at the poles, for the precipitation of this mass, the sudden downfall of snow there not only created the ice age but at once caught the tropical animals, burying and freezing them, and today we find them there with the tropical food preserved in their stomachs and the seeds of tropical plants in their hollow teeth. (See Vail's "The Earth's Annular System.") Then there is the true light pattern which the scientists have used erroneously for more than 300 years in explaining intensity variations; that of the issue of energy from a single luminous point. Imagine a single molecule of matter being illumined by such a point source. It can receive from it but a single light ray, which single ray can not possibly create visibility. Imagine the absurdity of saying that a fog bank is illuminated by the activity of a single one of its floating particles or that a gas flame was formed by the combustion of a single gas molecule. The truth is that the single point in a light source reveals the intrinsic intensity of the mass, while the number of these points in a flame establish its light creating value. For example: The combustion of a molecule of sperm gas, as in the candle flame, sets up a weaker luminosity than does the combustion of the kerosene gas molecule, as in a lamp flame, or the gas molecule in a gas flame. The size of the luminous body, or the number of such molecules at work, is what determines the light giving power of a flame. For this reason, to get a standard candle, it was necessary to size it so that it would burn a pre-determined number of grains of sperm per unit of time. Thus, by turning up a gas or a lamp flame we do not increase the intrinsic brightness of the flame but only its size. There are many light problems besides those of light patterns and intensity variations. Problems of eye protection, as against snow blindness, etc. The mechanics of the camera optics, to enable thingsto be enlarged and copies exact size, etc., on the film. The problem of the art of illumination as in the work of the illuminating engineer and the forester. The problem of the art of illumination as for the artist and the photographer, so as to enable students of the art classes to make portraits with their home window light, in any desired pattern of light and shade effect. The problem of the working value of lenses, or of the solid angle of the light pencils which they cast. With this the student can use grandad's spectacles and with cardboard make a camera that will function by strict known law, and take pictures, if desired, up to life size. The stops in this camera would be evaluated in units as easy to comprehend as units of distance and area, and the student would be able to fix these stops from what they should be able to learn in their study of physics in the schools. The problem of the brightness of subjects in unit terms. The problem of the speed of films and plates. The simple mathematics of exposure by division. And that of using the moving picture camera with precision. C. FRANCIS JENKINS (From the Richmond, Indiana, Item) C. Francis Jenkins, inventor of the motion picture projection machine and holder of more than 400 foreign and domestic patents, is dead at his home in Washington, Wednesday, June 6. Born near Dayton, Ohio, Mr. Jenkins spent his boyhood near Fountain City and Richmond. He attended Earlham College, accepted a position in Washington, and then became interested in inventions. Upon a visit to Richmond, June 6, 1894, Mr. Jenkins invited members of his family and friends to witness the operation of a motion picture machine. His projection machine was set up in the rear of Jenkins' Jewelry Store, and Richmond gained the distinction of being the first city in the world in which a motion picture exhibition was held. From that time on Mr. Jenkins devoted his genius to the perfection of many devices and instruments which gained him international fame. Radio photography, te'evision, radio movies, improvements on airplanes and hun He recognized no limits in the field of human achievement and believed every barrier in the way of scientific progress could be overcome. Like all geniuses, Mr. Jenkins was enthusiastic over the possibility of success in any project that claimed his attention. Equally as interesting was his belief that a great discovery usually had been the result of an avocation, a plaything during rest or leisure time. "Each has been the result of someone's riding a hobby, a kindly soul tinkering around in the woodshed with what the neighbors were pleased to call his 'crazy idea'," he said in an address here a few years ago. "I have always observed that a new thing always originates in a single brain, usually the brain of a poor man. It is not the product of great wealth and a great laboratory. Money only develops, it never originates. I guess because money does not work in a woodshed." Here is a truism which the boys and girls who are leav dreds of other practical and technical questions engrossed ing high schools and colleges by the thousands this month his inventive genius. should take to heart and ponder over seriously. Please mention The International Photographer when corresponding with advertisers.