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Professional Cameras

( Originally Published 1924 )

IT is not advisable for the amateur to invest in a professional type of camera, no matter how well he can afford to do so, unless he expects to engage in some branch of motion picture work which will prove profitable, for the advantages thus obtained are not great enough to justify the additional expense. However, in case some of my readers wish to get the best equipment obtainable, I shall briefly describe the professional cameras in use today in this country.

First, there is the old stand-by, the Pathe Studio Model. For many years this camera was the standard of the world, and it is widely used in the highest class studios today, and there are many cinematographers who would not consider using any other camera. Although this is true, it is also true that the Pathe is one of the least expensive of the truly professional cameras.

The Pathe camera, that is, the so-called camera unit, measures 4 3/4 x 8 x 12 inches, and weighs twenty-two pounds. This unit is the camera mechanism only. The magazines are of the outside type, and hold four hundred feet of film as do the magazines of all of the truly professional cameras. Both camera and magazines are covered with black leather and all metal fittings enamelled black. This prevents all disturbing light reflections. A peculiarity of this camera is that the broad side of the camera unit is toward the front, and the crank operates from the back. On the back of the camera is a dial which indicates the amount of film used and another which indicates the focus of the lens, so that scale focusing can be used without having to go to the front of the camera. Another door at the back covers the focusing aperture which is used in direct focusing. The camera is provided with both the 8:1 and the 1 :1 crank movements and reverse. The take-up is of the spring belt type, and as the driving belt is visible while operating the take-up can be checked at any time. The Pathe camera is regularly supplied with an automatic dissolve. The mechanism of this device is not the usual double shutter, but is operated by gradually closing a diaphragm. The fading of the light in the shutter dissolve has an accelerated motion. That is, at the beginning of the dissolve there is little change apparent, but as the dissolve progresses, the picture fades out with-a jump. This is not true with the diaphragm dissolve in which the fading of the light is uniform throughout the dissolve.

This dissolve must not be confused with the "iris-out." The effect upon the screen is a true fade, just as the fade made with a double shutter, but the effect is more uniform.

The Pathe camera has an adjustable shutter which is supplied for giving short exposures in photographing objects moving at a high rate of speed. The finder is of the ground glass type, is of large size and provided with a roomy hood. The finder swings so that it may be adjusted to show the exact field at any distance from the camera. This is an invaluable feature in close-up and trick work. The front of the camera may be removed to give access to the shutter and the dissolve mechanism, and a door in the back is opened to thread the film. The intermittent is worthy of note, for it is the original Pathe harmonic cam and shuttle, a type of intermittent which has been copied by the manufacturers of almost all high grade motion picture cameras. This is the type of intermittent in which the claws move in four straight lines, up, in, down, out instead of in a circle, flattened on one side.

This camera may be fitted with all of the usual "effects" and is in every way a professional camera of the highest type, yet one dealer at least, sells this camera, brand new, complete with Zeiss Tessar lens and two magazines for six hundred and fifty dollars.

Another high-grade camera is the Wilart. This camera is of all metal construction, and closely resembles the Pathe in general appearance. Indeed, it is often called "The American Pathe." The principal points of difference between this and the Pathe are: The Wilart is of all-metal construction which not only permits accurate action under any climatic conditions, but also does a great deal toward the elimination of "static," the bug-bear of cinematographers in cold climates. This is a branching, tree-like marking which is caused by tiny sparks of static electricity generated by the friction between the film and the gate. The Wilart camera is equipped with the more usual shutter dissolve. It has the usual dial footage meter, and also an in-built Veeder counter which records the individual feet of film used. It, of course, has a film punch, as have all professional cameras. The intermittent is of special design, but is a development of the harmonic cam and shuttle, actuated by the "Wilart Drunken Screw." There is also a view finder with a scale which permits it to be set to include the correct field of view at any distance from the camera.

Another high grade camera is the De Brie, also of French manufacture but closely imitated by the German Ernemann people. The De Brie camera is a small and compact walnut box, finished in natural wood.

The camera is self contained, the four hundred foot magazines lying side by side in the box. The first loop, which corresponds to the upper loop of the usual type of camera, is a spiral loop, which provides space both for the loop proper and for the lateral displacement of the film, causing it to feed accurately into the upper end of the gate. This camera is probably the highest type of news camera ever devolped, and is extensively used by professionals for work on location where the bulk and weight of the studio camera is an objection.

This camera has a unique arrangement whereby the focusing and diaphragm scales may be observed from the operating position at the back of the camera. The two movable elements of the lens mount have long rods attached. These extend beyond the limits of the side and top, respectively, of the camera box. These rods slide along other rods which are graduated. The focusing rod has four scales engraved upon it, one on each side, so that lenses of four different focal lengths may be used. The camera may be fitted with the usual Goerz or other "effects." It is provided with a direct focusing tube for vizual focusing, both the usual and the one to one crank movements and reverse. The dissolve is of the double shutter type. Film meter and punch are provided. This camera is also provided in the high-speed type for slow-motion photography. The regular model costs fifteen hundred dollars and the high speed model, three thousand dollars. The film produced, is, of course, as good as can be produced with any outfit. This camera has been recently introduced in a news model. This model is the same as the professional model, but is adapted for straight cinematography only. It costs three hundred dollars. With the professional focusing rods and other refinements, the news model sells for four hundred dollars. Many news men in the past have purchased the professional model at fifteen hundred dollars, so the new models, which will produce the same high grade film, will be welcomed by the news fraternity.

Some years ago the Bell & Howell cine-camera was introduced and rapidly rose to the peak of popular approval. This is the camera which is used in making the great majority of professional motion pictures and is regarded as the standard of perfection in cinecameras. It will be remembered, that in days past, when film stock was purchased plain and perforated by the user, that the perforations were made to con-form to the Bell & Howell standard. This firm also makes other standard cinemachinery, including perforaters, splicers, printers, polishers and so forth, all of the highest professional quality and incidentally selling at strictly professional prices.

The Bell & Howell camera is a "unit" outfit. That is, the purchaser buys the component parts best suited to his work and pays for only those parts necessary to his work. The camera sells for twelve hundred dollars. This consists of the camera case, shutter, dissolve mechanism, shuttle, turret and turret plate. The camera is utterly useless without the accessories which include : magazines, lenses, finder, footage meter, hand dissolve and so forth. The minimum operating equipment is usually thought of as the following: Camera, 50 mm. photographic lens, 50 mm. finder lens, finder, film meter, one double magazine, focusing glass and tripod, with cases for the complete camera. This equipment sells for approximately two thousand dollars. The usual professional equipment includes the Goerz effects, a 75 mm. photographic and finder lens and a 100 mm. photographic lens, the 50 mm. finder lens serving as a 100 mm. finder lens, having a square en-graved on the ground glass to serve as a guide, a prism focusing glass, a focusing microscope, the hand dissolve, range finder mounting for the finder, an auxiliary aperture plate for exact trick work and four extra magazines. The complete outfit, with lenses mounted in micrometer mounts will cost between three thou-sand and thirty-five hundred dollars. A high speed mechanism for slow motion work is supplied for seven hundred and fifty dollars additional.

This camera is an unusual looking affair, and to the uninitiated looks like anything but a camera. The most distinctive feature is the large double magazine, which locks on the top of the camera and holds four hundred feet of film.

The camera is of all metal construction and is constructed with the accuracy of a watch. The camera is fastened to the tripod by a dove-tailed projection which permits it to slide from side to side freely, yet remain at any position by virtue of a clamp which is easily released by one finger while mounting or de-mounting the camera. The camera has a turret plate on the front which carries four lenses at one time, and by releasing a catch-pin, any one may be revolved to position in front of the photographic aperture.

The shutter is large, measuring about six inches in diameter, machined from a comparatively heavy plate. This shutter is accurately balanced and acts as a balance wheel for the entire mechanism. It is of double construction, embodying the automatic shutter dissolve. The dissolve is thrown into action by pressure upon a small lever. When the fade-out is complete, a brake is thrown on automatically stopping the camera. Pressure upon a small button releases the brake and any desired amount of film may be wound into the magazines with the shutter closed. Of course, in operating the fade-in the action continues uninterruptedly from the opening of the shutter. The camera may be locked manually by revolving a milled ring which surrounds the shutter aperture dial.

There are two film meters provided. One a dial with manual reset pointer is used to record footage. of each individual scene which is used when such records are required by the producer. The other is a Veeder counter which records both feet and individual frames. This last feature is invaluable in trick work.

The take-up is of the spring belt type and as it operates in view of the operator, a constant check upon the take-up is possible. In filling the magazine, the film must be rewound so that the emulsion side is on the outside of the roll. The spools are about twice the diameter of the original wooden spool upon which the film is wound at the factory. I have known cinematographers who pulled a strip of film from the center of the roll until a hole was obtained which was large enough to slip over this spool, then by crossing the belt the film could be used without rewinding. This saves time, but wastes a great deal of film.

The shuttle mechanism is a wonderful piece of mechanism. The pins are accurately ground and are said to fit the perforation of the film to within a ten-thousandth of an inch. There are two pins, known as registering pins, which point backward and are fixed in position. These pins engage perforations at the top of the film. Then there are two other pins which move with the shuttle and actuate the film. The entire aperture plate moves backward, the moving pins move into the film and engage the perforations and pull the film down one frame, then the aperture plate, or more properly the gate moves forward, the fixed registering pins engage the perforations and the gate carrying the film is clamped firmly against the main aperture plate. The shutter then opens while the shuttle carrying the pins moves backward, upward and inward. Then the shutter closes and the process is repeated. The two registering pins ensure absolute accuracy in register of the film, no matter how many multiple exposures are made. The only thing which would render register inaccurate would be the mutilation of the perforation itself, and as there is no pull upon the registering pins, so accurate is the movement, this will not happen ordinarily.

The problem of focusing the motion picture lens is a difficult one. The finest possible accuracy must be obtained and this is very difficult. Some cameras have ground glass plates which swing into the aperture, but this necessitates fogging or cutting the film or both. Others punch a hole in the film so that a portion of the image falls upon a ground glass behind the film, yet this throws the focus out an amount equal to the thickness of the film and this is undesirable. Others focus upon the emulsion, but the emulsion is only translucent at best, so that fine focusing is difficult. The Bell & Howell camera focuses by a unique system. The photographic aperture is at the left of the operator and the photograph lens should be at the left of the turret. When it is desired to focus the camera the turret is released and revolved until the lens is at the right side of the turret. The camera is now moved to the left side of the tripod, and the lens is focused upon the ground glass focusing screen which is fixed in the focal plane. When the lens is focused, the lens is again revolved to the photographing position at the left of the turret, and the camera is moved to the extreme right of the tripod. The lens is now in exactly the same position in regard to the field which it occupied while focusing, so that the focusing field is identical with the photographic field. Thus the camera may be focused at any time without disturbing the film in any way.

There are two other features which are used in ultra fine work. Just above the usual focusing aperture is an auxiliary focusing aperture which takes a focusing microscope. This enlarges the image and focuses by aerial focus. This means that the image instead of being rendered visible by projection upon a ground glass, which no matter how fine has some grain, it is projected in air or in space, and is rendered visible by an optical system, just as the image projected by the objective of a compound microscope is rendered visible by the optical system of the ocular. This, of course, renders possible a focus much finer than can be obtained upon any grained surface. The second device is the micrometer lens mount. For ultra fine focusing, all the possible illumination is desired, so the diaphragm must be opened to full aperture and as the focus of any lens changes to some extent with various apertures, the focus, when obtained would be thrown out by setting the diaphragm. With the micrometer mount, the lens is focused at full aperture and then, when setting the diaphragm, the mount automatically compensates for the change. It must be understood that the change in focus by stopping down is so slight, that it would not be noticeable in contact prints or paper enlargements, and is so delicate that the inexperienced amateur could not discern it in focusing, so that the skill of the cinematographer is tried to the utmost in this ultra-fine focusing.

A bracket is furnished which attaches to the Bell & Howell tripod to support the trick "effects" so that there is no weight whatsoever on the camera or lens mount.

The magazines of the Bell & Howell camera are of the double type. That is, each magazine has two chambers, retort and receiver. These chambers are fixed and not interchangeable. The retort is filled with the unexposed film, the film lead out through the throat, into the receiver throat and fastened to the receiver spindle. The covers are then screwed into place and the magazine is ready for service. When about to load the film, a loop is pulled from the retort, leaving both ends of the film attached to their respective spindles, and the camera threaded. These magazines have a light-proof door which is closed tightly upon the film in each throat. When the camera door is closed a projection on the door presses a lever which opens these doors, so that in operation there is no pressure whatever upon the film. In operating the Bell & Howell camera, there is no pressure or friction what-ever upon the emulsion side of the film at any time while it is in motion.

I have used the word "effects" as a noun at various times and I shall now briefly describe these devices. First, there is some kind of support which varies with various cameras which serves to keep the axis of the effects in line with the optical axis. Then there is a revolving support fixed to this which permits the devices, as a whole, to be revolved about this axis. Upon these supports rest the effects themselves. First, there is the iris. This is a large iris diaphragm operated directly by lever or indirectly by crank and gears, but in any case, manually operated. When closed this causes a circle in a black background to be projected upon the screen. This circle grows smaller until the picture is blotted from the screen. The circle usually terminates at the center of the screen, but it may be shifted so that the operator may iris-out on any character in any portion of the screen. This device is some-times used in place of the fades, and in scenics it is most effective.

Then there is the double exposure device. This consists of a frame carrying two opaque leaves which open from and close toward the center and may be used vertically or horizontally. It is sometimes, but rarely, used as the iris is used, to open and close upon a scene. More often the lever is disconnected so that each half can be opened or closed independently of the other. Thus either half of the film may be exposed. Used in this way it is analogous to the old and familiar duplicator used on still cameras for double exposure work.

The square closing dissolve gives the same effect on the screen as the iris, but the opening is square instead of round. More properly speaking, it is rectangular with proportions relative to the proportions of the frame, that is 3:4. It is made like the double exposure device, but the leaves instead of meeting, cross each other, and the edges have an angle cut in them. The device is set obliquely in front of the lens, so that one long side of the opening is parallel to the bottom of the exposure aperture. When the lever is moved, both leaves move toward. each other, closing the square from all four sides.

The multiple exposure device is similar to the double exposure device, but it has interchangeable leaves with apertures which vary in size and shape so that any portion or portions of the film may be exposed successively.

These devices are known collectively as effects and those described are the original Goerz effects. There are now numerous complex irises and other effects upon the market, but they all follow the basic design of the Goerz effects.

The shadow box is sometimes included in the effects. This is in reality a filter holder, and serves to support the various filters used in cinematography. The filters are used for graduated rather than for orthochromatic effects. An iris may be obtained with amber instead of opaque leaves which is used in the same manner as a filter, holding back, but not obliterating the edges of the picture. The shadow box is also used to hold diffused edge masks when the proper shape cannot be obtained by the multiple exposure device. So to mask out a circle within the borders of the frame, a glass is used with an opaque spot painted upon it. It is also used to block out doorways and other irregularly shaped portions of the picture.

The use of the various effects adds a great deal to any picture and it is the facility with which they may be used in multiple exposure work which makes the professional cameras so much more expensive than the amateur models. A camera costing only two or three hundred dollars can be made to produce as good film for general use, in straight cinematography, as that exposed in the best of professional cameras. Trick work, and scientific work requiring fine focusing and kindred types of work are the ones which require the high-grade camera.

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