Pinhole camera

“ Serviceability and reliability are the outstanding features of the low-priced camera, and it is applicable to almost every branch of the craft.
Contrary to general belief, taking the "movies" is quite as simple as snap-shot photography with a Kodak. In the latter case you press the button; in the former you turn the handle; the camera does the rest. The rotation of the handle, a simple operation, performs every duty through the internal mechanism. It swings the shutter across the lens, moves the film intermittently through the instrument, and coils up the exposed film in its dark box. ”

“ But if both movements are to be completed simultaneously, the operator will require help. One person must sight the object and keep it in the picture by the manipulation of the two handles governing the respective movements of the tripod head, while the other confines his energies to turning the camera handle.
Although the moving-picture camera is built substantially and strongly, its mechanism is comparatively delicate. While it will withstand the hardest descriptions of legitimate work, it succumbs readily to brutal treatment. ”

“ The construction of the camera obscura is founded on the fact that the rays of light, when collected into a point either by being passed through a small hole or a converging lens, form an image of the objects from which they proceed at the point of meeting. This may be readily tried by piercing the shutter of a room with a small hole, and holding a piece of paper within a short distance of it. It will be noticed that the smaller the hole the more distant will be the image formed. ”

“ And while the great majority of the attempts to get them prove failures, the photographer—usually an amateur-needs only to provide an avenue in front of his lens a short distance, that is free from falling flakes by the use of a shelter such as a tree or porch. The slow snapshot necessary in cloudy weather will not stop the motion of the flakes nearest the camera and these passing through greater angles of space in equal length of time than those farther away, will blur on the negative. ”

“ When the sliding door of the compartment is down, the compartment is sufficiently light-tight to fulfill all the requirements of a camera. The movable carriage of the lens is mounted on two small glass tubes and runs between guides. A spring at its back end pulls it toward the position of focus for distant objects, where its motion is stopped by a pin. A long screw is passed through a, hole in the bottom of the camera box and enters the bottom of this lens carriage, so that an automatic arrangement outside and underneath the camera can regulate the focus. ”

“ In the ordinary stand camera used for still-life work, there is a bellows which can be racked to and fro to enable the subject to be focussed sharply upon the ground glass screen. The cinematograph camera has no bellows, and there is no fixed screen for focussing purposes. In the simpler and cheaper cameras, suited to amateur use, the operator is not troubled with focussing details at all, the lens being of a fixed focus as in certain types of snap-shot hand cameras; but in the more expensive instruments, designed for producing the finest classes of work, focussing facilities are incorporated. ”

“ On the main shaft is also arranged the shutter, E, which rotates [509] with the film-moving mechanism. Fig. 2 shows the simplicity of the camera. On the upper end of the box is the sensitized ribbon, which passes downward between guides before the lens opening. The bent ends of the cam operating bar, which give the fork, D, its reciprocating motion, are shown in Fig. 3. Fig. 4 is a general view of the instrument, showing the driving gear and film support. Fig. 5 shows the cinematograph camera in operation. It will be seen that the camera is very portable. ”

“ Pass through the holes, S S, an iron rod or a long needle, which must pass likewise through the upper angle of the triangles, forming the sides, (Fig. 1) . When your lens has been fixed on the round hole of the square your camera is complete.
The shade produces complete obscurity so that the operator can see in the middle of the camera the object or person he wishes to photograph.
In order to fix it on the photographic apparatus, one may fasten a wire, in the form of an elongated U, just below the mirror at E.
The Phantom Needle. ”

“ The Simplest Kind of a Camera. —When you can buy a real camera for two or three dollars it seems of little use to make one, so just consider the camera I shall describe as a scientific curiosity rather than an apparatus of utility.
Fig. 56. an easily made pin-hole camera
A. Cross section showing the notched strips.
B. The way the shutter works.
To make a pin-hole camera, so called because a pin hole takes the place of a lens, form a box of pasteboard or of thin wood 4 inches square and 8 inches long; cut a hole 3⁄8 of an inch in diameter in one end for the pin hole. ”

“ He knows that the film camera is more convenient, that it will load and unload in daylight, and as the films are much lighter and occupy less space than dry plates, he knows that the film camera is especially desirable for use at vacation time, when traveling, and on other occasions where light weight and the greatest convenience are necessary. On the other hand, he knows that the plate camera offers the advantage of ground glass focusing between each exposure—a very desirable feature to many as it insures absolutely sharp focus and does away with the estimating of distances. ”

“ Upon the top of the frame is bolted a two horse-power electric motor which is driven by a set of storage batteries; the combination of the turntable with a vertical adjustable enables the camera to be shifted so as to take in the required field. In the front of the camera is fixed a lens of great light-gathering quality which produces an image of exceedingly clear detail. Inside the camera is a strip of gelatine film two and three-quarter inches wide, and usually about one hundred and sixty feet in length, which is wound upon a small pulley and drum. ”

“ But by providing the loop an elastic feed is secured, and the film is jerked into position before the lens with the minimum of vibration and without any risk of tearing or displacement.
Threading completed the lower dark box is closed and secured, together with the side of the camera, so that the whole of the interior is light-proof. The camera should not be re-opened after photographing has commenced until the whole of the film in the loaded box is exhausted, or, if the supply is not used, until the dark-room is regained, unless the waste of a foot or two of film is a secondary consideration. ”

“ The camera has rising and falling front, actuated by rack and pinion, and this can be locked solidly at any point by merely pushing in the pinion. The front board is removable and is large enough to accomodate any lens. ”

“ It is essential that the apparatus for use in the air shall have high lens and shutter speed, means for rapid changing of plates, and anti-vibration suspension. Without these features a camera is of little use for aerial work. These requirements lead inevitably to greater complexity of design. One simplification over ground cameras, however, is brought about by the fact that all exposures are made on objects beyond the practical infinity point of the lens; consequently, all cameras are fixed focus. ”

“ For instance, in making a picture of an outdoor group of twelve or fifteen people, with an ordinary camera, they would have to be arranged in two or three rows to get good sized images, but with a Panoram they can be arranged in a semi-circle, at a given distance from the camera, and all appear in the picture in one row and of the proper relative size. Again, in making a landscape, the sweep of the Panoram lens will take in the complete view, while the scope of the ordinary camera could only permit a portion of it to be taken at one exposure. ”

“ The "Alpha," which [23] costs a little more, is full value for money, and is well worth the slightly increased price. This camera is fitted with a light-proof hinged front panel giving access to the adjustable shutter, which permits the opening of the latter to be varied within wide limits and thus enables extremely rapid movements to be photographed while running the machine at the normal speed. The spool boxes carry 100 feet of film of standard gauge in each instance, and for general all-round work, such as the recording of topical events, either model will be found perfectly efficient. ”

“ The film is a celluloid ribbon and is punctured near either edge, at intervals, so as to enable it to be gripped by the claws of the mechanism and moved forward intermittently a definite distance—three quarters of an inch—through the camera. This puncturing or perforation of the film is the most delicate of the whole cycle of operations. It can only be done by a machine of unerring precision manipulated with extreme care. The machines, though many are on the market, are somewhat expensive, and it is upon them that the steadiness of the picture on the screen depends. ”

“ The Premo No. 8 is an excellent illustration of the application of this idea. Designed for the amateur who wants a convenient, dependable plate camera at a moderate price, it is so carefully made and so simple to operate that it will produce remarkably good results for so inexpensive a camera.
It is equipped with our regular Planatograph lens, each one carefully tested, and the shutter is of the Kodak Ball Bearing type but supplied with bulb and tube instead of cable release. ”

“ The practice is to point the camera to the zenith if need be, to focus sharply, to to use the smallest stop, develop and select for final use according to the lighting, indeed, not always being very particular on that point. But, by elevating the 198camera a point of sight is taken different from that employed in taking the landscape; by focussing sharply, often using a lens drawing falsely, the clouds are rendered false in tone and false in drawing. ”

“ There is one great benefit accruing from the use of this apparatus. Unless wanton carelessness is displayed, one need not worry about under- or over-exposure. The paper negatives are coated with an exceedingly rapid emulsion of considerable orthochromatic quality, so that true colour-values are ensured.
A very noticeable feature is the ingenious focussing device. Instead of opening the camera and removing the film from the gate, as in the ordinary cinematograph camera, one has merely to slide a stop projecting from the back of the camera to the length of its slot. ”

“ Of course, two laths of wood can be used, merely resting them on the top of printing frame and camera, but the other plan is preferable, the arrangement being more complete and adaptable to both day and artificial light, and also more rigid, especially when the camera is sloped toward the sky.
The ordinary camera may be used, but a carrier to take lantern plates must be used in the dark slide. The ordinary lens may be used unless of inordinately long focus, when it becomes inconvenient on account of the great distance between negative and lens. ”

“ Though the single acromatic lens answers very well for copying engravings; taking views from nature or art, for portraits the double should always be used. The extensive manufacture of the most approved cameras, both in Europe and in this country, obviates all necessity for any one attempting to construct one for their own use. Lenses are now made so perfect by some artisans that, what is called the "quick working camera" will take a picture in one second, while the ordinary cameras require from eight to sixty. ”

“ The scenes most worthy of record frequently give little warning of their approach and are of short duration; and, unless the camera is one which can be quickly manipulated, the opportunity will be gone before the record can be secured. The mountaineer is, therefore, confined to the use of a simple, light camera of small and convenient dimensions. The opinion is widely expressed in books on mountain photography that good results are only obtainable with stand cameras and glass plates—the heaviest and most inconvenient type of photographic equipment. ”

“ It is well known by amateur photographers that when a person is focussed a certain distance from the camera, if he steps towards the instrument the focus is immediately255 upset. When the individual is taken in motion, and in such a way that he comes right up to the lens, this difficulty is enhanced. It is impossible to keep adjusting the focus of a cinematograph camera while the subject is advancing, because the focussing tube is obstructed by the passing of the film through the gate. ”

“ There, just where they had left it, was the camera, the motor clicking away industriously. It worked intermittently, running for five minutes, and then ceasing for half an hour, so as not to use up the reel of film too quickly. Also, it made a diversity of street scenes, an automatic arrangement swinging the lens slightly after each series of views, so as to get the new ones at a different angle.
“Now we’ll show you,” said Blake, as, having noted that all the film was run out, and was in the light-tight exposed box, he opened the camera and showed the harmless mechanism. ”

“ Naturally, as the intricacies of the craft are mastered, the tyro will wish for a more elaborate apparatus. He can gratify his ambitions in accordance with his progress, or with the improvement in his financial position.
The mechanism of the modern cinematograph [26] camera is very simple in its character and very easy to understand. The necessary parts are very few in number. In all cameras the chief object is to effect the forward intermittent movement of the film at regular intervals and for a defined distance. ”