[The immense part played by aerial photography in the prosecution of the war is naturally realized by photographers, a very large number of whom have been practically engaged in carrying it on. But perhaps the magnitude of the scale is not a matter of common knowledge, and therefore we embrace the opportunity of reprinting from the "Daily Telegraph" of Monday last an article which presumably embodies official figures. It is interesting to find that in the essential matters of cameras and lenses the British forces were better equipped than the German. The fact has recently been the subject of remark as regards lenses, and the writer of the 2 notes printed below describes, it will be noticed, the same superiority in respect to cameras. Eds. "B. J."]
When hostilities broke out in 1914 aerial photography was still in its primitive and experimental stage. A considerable amount of pioneer work had been done both from balloons and aero planes; a small but valuable literature was arising; but the impetus of war was required, with the aid of the immense scientific and technical resources behind the Royal Air Force, to exploit its possibilities. Some idea of the progress made can be gained from the fact that on the Western front alone during the last ten months of war no tower than 264,605 Royal Air Force negatives were taken in the air over German territory, and the gigantic total of 5,800,000 prints was made from these negatives for the use of the Intelligence Staff.
The most recent types of Royal Air Force cameras are very highly finished pieces of work. .The lens itself is shielded in a deep tube which faces vertically downwards, thus preventing direct sunlight falling upon it. At the other end of the camera is a steel chamber, containing the automatic device for changing the plates after each exposure. The entire apparatus is securely fastened to the side of the machine, and u connected by a wire with the observer's seat. The pressure of a lever is sufficient to expose a plate and to bring a new plate into position. The German cameras, as recently exhibited in the Strand, lack many of the exquisite mechanical refinements of the British instrument, particularly the ingenious device by which the plates are automatically changed in the air, without any attention whatever from the pilot. This striking British invention ha enabled many excellent and valuable photographs to be taken while the machine itself has been under heavy fire both from the air and the ground.
High-Speed Photography.
Anyone who has tried to take a snapshot from the carriage window of an express train realizes the difficulty experienced in obtaining a negative entirely free from movement. The same difficulties are, of coarse, experienced in taking photographs from the air. A modern aero plane is really a traveling observation platform moving at from fifty to a hundred miles an hour. As the pace of the machine cannot be altered, the object to be taken must be "snapped" as it slips swiftly by beneath the machine. Aerial photography is, therefore, high-speed photography of a special kind. An aerial photograph is almost always under-exposed, and this calls for exceptional treatment when the plates come to be developed. Apart from this peculiarity, however, it is the definite policy of the Royal Air Force to specialize in very thin negatives. A dense negative takes far too long to print by artificial light. A thin negative enables prints to be made in about three seconds. In this way a trained Royal Air Force photographer can print and develop as many as eighty separate enlargements in the course of an hour.
For this scientific work the Royal Air Force has trained large numbers of highly skilled workers. In the model dark-rooms at the Central School of Aerial Photography every candidate for acceptance as a R.A.F. photographer must first pass a severe test, designed to reveal his suitability or otherwise for the work. He is then given a month's practical intensive training, particular attention being paid to the processes of development, and to the enlargement of negatives by artificial light. Much importance is attached to the rapidity with which these enlargements ran be produced, for the fate of a battle may depend upon the promptness with which large scale copies of a vital subject can be supplied to the Intelligence Staff. After a further course at a training centre in England, the airman-photographer would proceed to a service squadron overseas and be assigned to a photographic section working with a recon naissance Bight. Such a "section" usually consists of a technical non-commissioned officer and about seven men, who take in torus the more confined and laborious aspects of the work. One man will “load” the magazines with unexposed plates, another will fix the cameras to the machines prior to flight, and receive them on return; others are detailed for developing, washing, drying, and plotting the negatives. Several men are constantly engaged in tin enlarging room, exposing and developing as many as 100 prints in an hour.
Before an Offensive.
It is during the strenuous days preceding a big offensive that photographic activity raises to its maximum. During the successive big drives made by the British in France during the summer and autumn of last year, the entire field of operations was photographed over and over again. If a new series of enemy trenches were constructed during the night, a R.A.F. reconnaissance squadron would bring home photographic evidence of the fact on the following morning. It was no uncommon thing for as many as 11,000 negatives to be made on the Western front alone during a single week preceding an important advance.
In addition to this vast work of aerial reconnaissance, photography was also extensively used for verifying the results of artillery fire, and for recording the precise effects of bombs dropped from the sir. The very Inking photographs of Frankfort, Mannheim, Mets, Sablon, etc., recently published in the Press, were actually taken during the raids upon those towns. Another valuable development was the application of the stereoscope to war intelligence. By taking two photographs of the same object, say an enemy trench system, at an interval of a few seconds, a striking stereoscopic effect is obtained which throws all the ramparts and other elevated portions of the enemy work into high relief. In this way the principal difficulties to be encountered by the attacking party can be foreseen.
Aerial photography is destined to become one of the big new industries of the future. The topographical surveys of to-morrow will be photographic surveys; the school and commercial atlases will be photographic atlases. Exploration, commerce, scientific research must all benefit by an industry which may well grow to very largo proportions. In this field of post-war industrial activity, Britain will inevitably take a foremost place, for she already has at her command in Royal Air Force personnel some of the most highly trained specialist photographers in the world.
When hostilities broke out in 1914 aerial photography was still in its primitive and experimental stage. A considerable amount of pioneer work had been done both from balloons and aero planes; a small but valuable literature was arising; but the impetus of war was required, with the aid of the immense scientific and technical resources behind the Royal Air Force, to exploit its possibilities. Some idea of the progress made can be gained from the fact that on the Western front alone during the last ten months of war no tower than 264,605 Royal Air Force negatives were taken in the air over German territory, and the gigantic total of 5,800,000 prints was made from these negatives for the use of the Intelligence Staff.
The most recent types of Royal Air Force cameras are very highly finished pieces of work. .The lens itself is shielded in a deep tube which faces vertically downwards, thus preventing direct sunlight falling upon it. At the other end of the camera is a steel chamber, containing the automatic device for changing the plates after each exposure. The entire apparatus is securely fastened to the side of the machine, and u connected by a wire with the observer's seat. The pressure of a lever is sufficient to expose a plate and to bring a new plate into position. The German cameras, as recently exhibited in the Strand, lack many of the exquisite mechanical refinements of the British instrument, particularly the ingenious device by which the plates are automatically changed in the air, without any attention whatever from the pilot. This striking British invention ha enabled many excellent and valuable photographs to be taken while the machine itself has been under heavy fire both from the air and the ground.
High-Speed Photography.
Anyone who has tried to take a snapshot from the carriage window of an express train realizes the difficulty experienced in obtaining a negative entirely free from movement. The same difficulties are, of coarse, experienced in taking photographs from the air. A modern aero plane is really a traveling observation platform moving at from fifty to a hundred miles an hour. As the pace of the machine cannot be altered, the object to be taken must be "snapped" as it slips swiftly by beneath the machine. Aerial photography is, therefore, high-speed photography of a special kind. An aerial photograph is almost always under-exposed, and this calls for exceptional treatment when the plates come to be developed. Apart from this peculiarity, however, it is the definite policy of the Royal Air Force to specialize in very thin negatives. A dense negative takes far too long to print by artificial light. A thin negative enables prints to be made in about three seconds. In this way a trained Royal Air Force photographer can print and develop as many as eighty separate enlargements in the course of an hour.
For this scientific work the Royal Air Force has trained large numbers of highly skilled workers. In the model dark-rooms at the Central School of Aerial Photography every candidate for acceptance as a R.A.F. photographer must first pass a severe test, designed to reveal his suitability or otherwise for the work. He is then given a month's practical intensive training, particular attention being paid to the processes of development, and to the enlargement of negatives by artificial light. Much importance is attached to the rapidity with which these enlargements ran be produced, for the fate of a battle may depend upon the promptness with which large scale copies of a vital subject can be supplied to the Intelligence Staff. After a further course at a training centre in England, the airman-photographer would proceed to a service squadron overseas and be assigned to a photographic section working with a recon naissance Bight. Such a "section" usually consists of a technical non-commissioned officer and about seven men, who take in torus the more confined and laborious aspects of the work. One man will “load” the magazines with unexposed plates, another will fix the cameras to the machines prior to flight, and receive them on return; others are detailed for developing, washing, drying, and plotting the negatives. Several men are constantly engaged in tin enlarging room, exposing and developing as many as 100 prints in an hour.
Before an Offensive.
It is during the strenuous days preceding a big offensive that photographic activity raises to its maximum. During the successive big drives made by the British in France during the summer and autumn of last year, the entire field of operations was photographed over and over again. If a new series of enemy trenches were constructed during the night, a R.A.F. reconnaissance squadron would bring home photographic evidence of the fact on the following morning. It was no uncommon thing for as many as 11,000 negatives to be made on the Western front alone during a single week preceding an important advance.
In addition to this vast work of aerial reconnaissance, photography was also extensively used for verifying the results of artillery fire, and for recording the precise effects of bombs dropped from the sir. The very Inking photographs of Frankfort, Mannheim, Mets, Sablon, etc., recently published in the Press, were actually taken during the raids upon those towns. Another valuable development was the application of the stereoscope to war intelligence. By taking two photographs of the same object, say an enemy trench system, at an interval of a few seconds, a striking stereoscopic effect is obtained which throws all the ramparts and other elevated portions of the enemy work into high relief. In this way the principal difficulties to be encountered by the attacking party can be foreseen.
Aerial photography is destined to become one of the big new industries of the future. The topographical surveys of to-morrow will be photographic surveys; the school and commercial atlases will be photographic atlases. Exploration, commerce, scientific research must all benefit by an industry which may well grow to very largo proportions. In this field of post-war industrial activity, Britain will inevitably take a foremost place, for she already has at her command in Royal Air Force personnel some of the most highly trained specialist photographers in the world.
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