Equipment for Color-Photography – Photo-Era Magazine, 1920
Occasionally when I show friends and acquaintances an old camera I'm fixing, one from before the invention of modern color film, the person I'm talking to is surprised to learn that cameras such as, for example, the No. 2 Brownie I'm showing them is compatible with color film. I often like to then show off the photo of the Emir of Bukhara below to my companion, and ask them to guess the age of the photograph. I don't think anyone I've talked to has yet to guess anywhere near 1911, the actual date of this particular photo.
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| The Emir of Bukhara, Alim Khan Sergey Prokudin-Gorsky, 1911 |
It doesn't seem commonly known to those who are unfamiliar with or uninterested in the history of photography, but color photography, despite being fairly uncommon before the introduction of Kodak's color film in 1935, still goes back in one form or another almost as far as photography itself.
I came across the following article while reading a copy of Photo-Era Magazine from 1920. In it, the author discusses the practical challenges of color photography in 1920, both from the challenges of choosing the right camera and lens, to the specific issued with using Autochrome or Paget glass plates (these were presumably the two dominant processes for color photography in 1920). On that note, I recently read about a person who's producing and selling black and white negative plates today, in 2020; I can't help but wonder if someone like him might be able to reproduce a version of the Autochrome plates that this article mentions. With more and more people exploring photography processes, sometimes as old as the wet plate process, how long will it be before
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| World War 1 Nieuport 23, 1917 Medium: Autochrome plate |
Equipment for Color-Photography
ROBERT M. FANSTONE,
Photo-Era Magazine, 1920
MANY beginners in color-photography are inclined to pay too little attention to features desirable in their apparatus, and though the manufacturers of the materials used for various methods frequently state that any ordinary camera may be used, the process itself will be facilitated, and success assured if the photographer carefully examines his apparatus, with a view to its modification, if this is needed, according to the peculiarities of the particular process that he intends to work. I hope, by stating what is desirable in the way of apparatus, to forewarn the beginner against possible pitfalls, and also to assist the advanced worker who is not getting results as good as he desires.
With regard to the camera itself, I have found nothing so suitable as the ordinary view-outfit, and its most desirable feature is rigidity. Exposures for color-photography, even under the most favorable conditions, are long, and if the outfit is not perfectly firm when set up, trouble on this score is likely to occur. I have found that a camera that has never given any trouble when employed for ordinary out-of-door work, gave badly blurred negatives when used for color work in the deep shadow of the woodland, when the exposures were very long. Though most generally found upon the modern view-camera, the swing back and front is a great help in color work by reason of the fact that they facilitate focusing without stopping down. The value of this will be seen later.
The hand-camera, even when supported on a tripod, leaves much to be desired in the matter of rigidity, and considering that with all the modern color-processes the best result is obtained only with a full exposure, this is hardly in its favor. Of course, I do not mean to infer that good results cannot be obtained with any but a view-camera, but merely as experience has shown me to indicate what is best. Snapshot-exposures, with the camera held in the hand are impossible except under the most favorable conditions.
A shutter is not to be regarded as essential, and may even give trouble from vibration, if the exposures are very long. I always use the lens-cap when the exposure, as it often does, runs into twelve seconds, or more, and find that this is superior for long periods to the best of shutters. In the case of roller-blind shutters, operated by a pneumatic release, reliance cannot be placed on the instrument remaining open for a long period at "bulb," and if used at "time," trouble is apt to arise from vibration when pulling down the blind, to start the exposure; hence my preference for the cap.
While on the subject, it is perhaps as well to point out that the rigidity of the tripod should not be overlooked.
One of the most important points that should engage the attention of the color-photographer is, that his plate holders should be suitable for the requirements of the particular process that he is working; but I have known many who have overlooked this altogether. Both the Autochrome and Paget processes differ very considerably in their requirements in the matter of plate holders. With the former process, owing to the extreme delicacy of the surface of the plate–which is exposed glass-side towards the lens no pressure of springs, or the separating plate of the double plate holders, may be permitted, or an abrasion of the film is certain to result. On the other hand, when working the Paget process, it is not only most important that there should be springs on the plateholder, but also that they do their work effectually, in bringing the negative plate into perfect and entirely uniform contact with the taking series, in order that a perfect dot formation may be obtained. Neglect of this, which allows of uneven contact between plate and screen, produces a transparency that is color-correct in portions only, and those working the process should pay every attention to this matter which is one upon which the success of the whole process mainly depends. I prefer, for both Autochrome and Paget color-work, double book form placeholders or the American block-form holder, in preference to the single metal pattern, by reason of the fact the double plateholder allowes ample room for the plate. I have used the single metal-slides for the Autochrome process, taking great care to prevent abrasions of the plate from the back of the slide. This must be quite free of dents, etc. The single metal-slide is not, however, so well adapted for the Paget process, as it is difficult to get the two plates into the space only intended for one, unless the screen and plate are upon the specially thin glass issued by the makers for these slides, but even then there is some doubt about obtaining perfect contact. When carrying Autochromes in double plateholders, I take out the metal-separators and springs and load each plate holder with two plates, using the special cards issued by the makers for this purpose, as separators. For the Paget process I use one plate in cache plate holder, owing to the fact that if two exposures were loaded into each plateholder, the four plates would make a very tight fit when the springs are in position, and these would either tend to crack the plates, or to force the plateholder apart at the middle. I insert the screen and plate in the plateholder, taking note which shutter must be drawn for the exposure; on the back of the plate is laid a piece of dead black card, and on this the springs: the plateholder is then gently closed, the springs forcing the plates into even contact. Speaking of springs reminds me to mention that the single central spring fitted to the center of the metal holder divisions, is totally inadequate; my own are made from old pieces of clock-spring, covered with black velvet, in order to prevent their scratching. They are about two inches less in length than the width of the plate for a 44 x 62, are bent into a slightly concave shape, and placed in position in the slide with the ends resting upon the car-separator. They should be about two inches from the top and bottom of the plate. These springs should not be too strong. On one occasion, I unthinkingly used a couple of springs from the back of an old 34 x 44 printing frame; they forced the holder apart at the middle, and apart from fogging the particular plate, warped the holder very badly.
It is, perhaps, almost superfluous to add that everything inside the camera and plate holder should be perfectly dead black. This is far more important in color-work than in the ordinary branches of photography, since reflected light or halation may cause degradation of color in the finished result.
That the lens is fully color-corrected is of primary importance for all color-photography, and for this reason experience teaches me to favor one of the modern anastigmat in preference to one of the older R.R. pattern, since these may not be so carefully corrected of chromatic aberration. Another great advantage offered by the anastigmat is, that it will cover the plate sharply to the margins without stopping down, which may be necessary with an R.R. or other lens not having a flat field. Stopping down is to be avoided as much as possible, as this in practice tends to produce results that are devoid of the more subtle gradations. I am inclined for this reason to recommend a lens of fairly short focus for the plate in use, owing to the ease with which a subject in different planes may be focused sharply at a large aperture. If, however, the photographer does not possess an anastigmat, an R.R. or good large-aperture portrait-lens will serve. An important point is that the glasses of the lens itself must be free of any trace of discoloration. It sometimes happens that through the decay of the cementing compound, by reason of damp, improper storage, or other cause, the glasses of some lenses have a decidedly yellow or brown tint, which may upset the carefully adjusted lens filter. I was asked once why a certain amateur photographer's color-transparencies lacked the brilliant colors that the process was capable of producing, and had instead a brownish tint. After some investigation, the cause was traced to the fact that the lens was a very old and discolored instrument: indeed, sufficiently so to form quite a serviceable yellow filter, for orthochromatic plates. What has been said in this connection may be taken as applicable to all color-processes, especially to the Autochrome, and Paget, and perhaps in a slightly lesser degree to the making of color-sensation negatives, for three-color work. Lenses should never be stopped down below F/16.
We have heard little of color-photography with a telephoto lens, and I must confess to having little experience with it, but in the classes of work for which it is designed I can imagine no more valuable tool than one of the large-aperture telephoto lenses with a relatively short back focus such as the Telecentric or Adon. The older telephoto lenses are not so well suited for color work, by reason of the fact that they work at a small aperture; and their definition, upon which enough of the success of the picture depends, is very poor.
The soft-focus lens, owing to the reason that its particular feature is obtained by partial color correction, is hardly a suitable tool for color-photography, but it is to be hoped that with the advance of the latter a lens of this type may be devised to give us some of the pictorial advantages that it now offers for monotone work.
Of course, only filters suited to the process, as issued by its manufacturer, should be employed. I have found that sometimes these vary in color, but this will not affect their work, as they are carefully tested before sending out. Preferably, they should be mounted in optically flat glass, and every care taken of them. Experience teaches me that the best place for the filter is between the components of the lens, or if fitted in a cell, slipped over the back combination. There is a reason for this latter course. If the lens has not been perfectly color-corrected, the filter may prevent any ill-effects from this, but if it were fitted to the front of the lens, such would not be possible. It is most important that no light is allowed to reach the plate, except through the filter, such as would happen if the latter fitted loosely, and this is one objection to the plan of using a thin circle of gelatine between the components of the lens, as it is almost impossible to obtain a perfect fit, and white, or other light reaching the plate other than through the filter causes the color-photograph to be of a blue, or violet tint. When using unmounted gelatine filters, I make a practice of cementing each between two circular pieces of thin black card board, with the centers removed, leaving about an eighth of an inch all round to act as a cell, the outer circumference of the cell fitting quite tightly into the lens mount. This also saves spoiling the filter through handling the gelatine surface with hot or damp fingers, which is frequently done. For the Autochrome process a special screen-holder is supplied to fit on the inside of the camera, which should always be used when the camera will permit. With the view-camera there is always room on the inside of the front for this, but the compact folding pocket-camera does not always permit of this procedure. The solution of the difficulty lies in having the filter mounted in a well-fitting cell, to slip over the back combination of the lens.
An exposure-meter is of great importance if waste is to be avoided and the production of perfect results is to be the rule, and not the exception. I recommend a meter that makes an actual light-test, in preference to one of the published tables, or calculating-devices working upon a system of scales to be mentally adjusted by the photographer. Special colorplate-meters may be obtained, but there is really no need of these, though the Watkins Company supplies an interchangeable color-dial for their Bee meter. This is a great help, and simplifies matters considerably.
Of our old friend, much abused and ill-esteemed, that most of us still cling to–the darkroom lamp, though it may be fitted with a "safe light,"–I would point out that no light is "safe" for color plates, and the lamp should be simply used as a means of seeing what is wanted in the room, and in aiding the photographer's sense of touch, and not for the purpose of peering at the developing-plate in its early stages. I use several thicknesses of the safe-light paper issued by the makers of the particular plates that I happen to be working, cemented between two pieces of plain glass with a solution of Canada balsam, and bound up with lanternslide-binding-strips. This fits into the darkroom lamp in place of the usual screen. It is to be noted that for powerful illuminants a greater number of sheets must be used than may with safety be employed with a candle.–The British Journal.
Photo extras originally published with article:
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| 2020 | T C P | www.wideaperture.org |
