Most professional photographers would be surprised if they were told that in the matter of lens equipment they were far behind many enthusiastic amateurs, but we believe that we are correct in making this assertion. The fact is, that the professional is rather apt to put all his eggs into one basket, or, in other words, to invest in a few first-rate lenses and to consider that he has done all that is needed. He selects lenses for the size of the plate he generally works, and, so far as it goes, this is quite correct; but he seldom has anything to fall back upon for any job which may require one of a different focal length. It is remarkable that this is more likely to be the case with the photographer of to-day than it was a quarter of a century ago. Then it was not uncommon to find an equipment of a complete set of portable symmetricals, twelve in number, ranging from three to, twenty-one inches in focal length, the first ten fitting the same flange and in many cases having the lens cells interchangeable, so that even a variation of half an inch in focal length could be obtained. There were also "casket" sets, usually not of the finest optical quality, but good enough when used with small apertures, which gave an even greater range at a very reasonable cost.
The portrait man does not, of course, need such a variety of tools, but the man who is willing to take on any class of work frequently finds that he cannot do exactly as he wishes, and, what is more important, what his client wishes, because of his imperfect equipment. This state of things can easily be remedied at quite a small cost if it be borne in mind that a comparatively poor lens works nearly as well as an expensive one if it be possible to use a small aperture. Another point to be remembered is that with modern enlarging methods at our command it is not always necessary to limit ourselves to one particular size of plate, since, if we can get our subjects, it is easy to make prints of a larger or smaller size as may be required.
Let us take a few examples of possible orders and how they may be executed, or, to be more precise, how such orders have been executed. An extremely wide angle view of a street scene was required to show the disadvantages which would result to a shopkeeper if a railway viaduct were put near his premises. No orthodox lens would give the necessary view angle, but by using a four-inch lens which happened to be at hand, a negative was made upon a whole plate, which did just what was wanted: it gave the width of the picture well defined, and when the top corners were blocked out a 15x12 enlargement was made which did good service in court. Now, how many photographers have a decent four-inch wide angle lens in stock! Yet it is not an expensive tool, and if not paid for by the one job, its possession helps to build up a reputation for efficiency which leads to future orders. Such a lens is not only useful for outdoor work, but for enlarging when only a moderate length of bellows is available. If it be necessary to take a mall head out of a group, a considerable degree of enlargement can be obtained directly instead of having to resort to a second enlarging process. Conversely, such a small lens is of great value for making reductions with the enlarging lantern. If a copy, say, an inch by three-quarters, or less, has to be made from a cabinet negative it is easy to do so.
Going to the other end of the scale it is a rare thing to find a telephoto lens in the hands of the ordinary photographer; yet is a most useful instrument for many purposes besides taking distant views. We remember some years ago, when the original Adon was introduced, being told by a large firm who specialized in catalogue work that they had been recommended by an amateur to try a telephoto lens for the photography of small articles, with the result that they had greatly improved the perspective in very case to the satisfaction of their customers and their own profit.
While comparatively cheap lenses of the old rectilinear construction are capable of doing much useful work, we should not recommend their purchase if funds permit of more modern instruments being obtained, for when a lens is being used for copying or in the enlarging lantern at an extension which is many times its focal length, a large aperture is of great advantage, the difference in luminosity between one having an initial aperture of f/6 and f/16 being very noticeable, and if such lenses are of the "convertible" type, giving two or three focal lengths, their utility will be increased. Still, before purchasing new lenses it is as well to take stock of what lenses are on hand, and to make a note of their focal lengths. If duplicates of any one size are found one should be sold or exchanged, so as to secure further variety.
It may be found that although suitable lenses are available, there is no means of using them upon large cameras or enlarging lanterns, and it is therefore advisable to have them adapted to the flanges already upon such cameras. This can be done at the cost of a very few shillings, and in the case of modern instruments it is not necessary to part with the lens or large flange, as these will be of standard and it will only be necessary to mention the diameter. For a makeshift, a very good plan is to cut a hole in a piece of card so that the lens thread will just go through, securing it by screwing on the flange at the back, the card being attached to the camera front by means of four drawing pins.
Supplementary lenses of the Planiscope type will often prove useful, to shorten the focal length of lenses which will not give the desired angle or magnification, but it will usually be found necessary to work at a very small aperture when these are used, as the corrections of the original lens are upset. However, for this class of work speed is usually not necessary. A makeshift Planiscope may be made by attaching an ordinary small single lens, such as the front of a small portrait lens or one of the combinations of a rapid rectilinear, by means of a cardboard ring This sound rather crude, but we have known it to be done with success.
The portrait man does not, of course, need such a variety of tools, but the man who is willing to take on any class of work frequently finds that he cannot do exactly as he wishes, and, what is more important, what his client wishes, because of his imperfect equipment. This state of things can easily be remedied at quite a small cost if it be borne in mind that a comparatively poor lens works nearly as well as an expensive one if it be possible to use a small aperture. Another point to be remembered is that with modern enlarging methods at our command it is not always necessary to limit ourselves to one particular size of plate, since, if we can get our subjects, it is easy to make prints of a larger or smaller size as may be required.
Let us take a few examples of possible orders and how they may be executed, or, to be more precise, how such orders have been executed. An extremely wide angle view of a street scene was required to show the disadvantages which would result to a shopkeeper if a railway viaduct were put near his premises. No orthodox lens would give the necessary view angle, but by using a four-inch lens which happened to be at hand, a negative was made upon a whole plate, which did just what was wanted: it gave the width of the picture well defined, and when the top corners were blocked out a 15x12 enlargement was made which did good service in court. Now, how many photographers have a decent four-inch wide angle lens in stock! Yet it is not an expensive tool, and if not paid for by the one job, its possession helps to build up a reputation for efficiency which leads to future orders. Such a lens is not only useful for outdoor work, but for enlarging when only a moderate length of bellows is available. If it be necessary to take a mall head out of a group, a considerable degree of enlargement can be obtained directly instead of having to resort to a second enlarging process. Conversely, such a small lens is of great value for making reductions with the enlarging lantern. If a copy, say, an inch by three-quarters, or less, has to be made from a cabinet negative it is easy to do so.
Going to the other end of the scale it is a rare thing to find a telephoto lens in the hands of the ordinary photographer; yet is a most useful instrument for many purposes besides taking distant views. We remember some years ago, when the original Adon was introduced, being told by a large firm who specialized in catalogue work that they had been recommended by an amateur to try a telephoto lens for the photography of small articles, with the result that they had greatly improved the perspective in very case to the satisfaction of their customers and their own profit.
While comparatively cheap lenses of the old rectilinear construction are capable of doing much useful work, we should not recommend their purchase if funds permit of more modern instruments being obtained, for when a lens is being used for copying or in the enlarging lantern at an extension which is many times its focal length, a large aperture is of great advantage, the difference in luminosity between one having an initial aperture of f/6 and f/16 being very noticeable, and if such lenses are of the "convertible" type, giving two or three focal lengths, their utility will be increased. Still, before purchasing new lenses it is as well to take stock of what lenses are on hand, and to make a note of their focal lengths. If duplicates of any one size are found one should be sold or exchanged, so as to secure further variety.
It may be found that although suitable lenses are available, there is no means of using them upon large cameras or enlarging lanterns, and it is therefore advisable to have them adapted to the flanges already upon such cameras. This can be done at the cost of a very few shillings, and in the case of modern instruments it is not necessary to part with the lens or large flange, as these will be of standard and it will only be necessary to mention the diameter. For a makeshift, a very good plan is to cut a hole in a piece of card so that the lens thread will just go through, securing it by screwing on the flange at the back, the card being attached to the camera front by means of four drawing pins.
Supplementary lenses of the Planiscope type will often prove useful, to shorten the focal length of lenses which will not give the desired angle or magnification, but it will usually be found necessary to work at a very small aperture when these are used, as the corrections of the original lens are upset. However, for this class of work speed is usually not necessary. A makeshift Planiscope may be made by attaching an ordinary small single lens, such as the front of a small portrait lens or one of the combinations of a rapid rectilinear, by means of a cardboard ring This sound rather crude, but we have known it to be done with success.
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