A Boy's Workshop: With plans and designs for in-door and out-door work

by Harry Craigin

While there are several instruments in the market with which the negative can be taken, most of them are so costly as to be beyond the reach of a boy or a girl with a limited supply of pocket money for a vacation trip; hence I shall choose one that is not only very cheap, but which I know by experiment will perform the work for which it is intended. It is the invention of a young man who has a practical knowledge of photography, and is called the “tourograph.”

At first sight it is a small mahogany box, eight by ten inches broad, with a strap by which one can carry it. But by pulling out a slide in front a lens is revealed; and by drawing out another slide on the top an inner box is shown full of negative plates. This smaller box is fitted in position on top of the larger one, so that the plates, one at a time, can be dropped into a carrying-rack turned by a screw, in the dark chamber below. This plate having been placed in focus, the lens is uncapped for a few seconds, then recapped, and the glass is returned to the box above, where it is kept till evening, or until a favorable time for development. In this way all the plates—eight or ten—in the box may be exposed, and their places filled with fresh ones later on.

The camera is supported upon a tripod, or three-legged stick, which can be closed up until not much larger than an alpenstock.

This is the outline of the mechanical operation necessary to secure the negative. The plates, being ready prepared and packed in little boxes of a dozen each, are transferred to the camera at night, or in a dark room by day, by the aid of a red light. This is obtained by placing a roll of red or orange-colored paper—made expressly for this purpose—around a lamp or candle, as the light that shines through a medium of this color is non-actinic, or without the power to produce chemical change in the very sensitive plates. You now have a plate with a latent image of the picture you desire to retain; this plate must pass through a chemical operation before that image will appear.

Imagine yourself in a darkened room illuminated only by the red light, with a plate in your hand on which you fondly hope there is a duplicate of the scene before which you had set up the instrument. To all appearances it is a plate of plain glass, one side covered with a film of gelatine, and if you hold it to the light nothing appears to indicate the change that has taken place in that film since it was exposed to the light. The question is, how to bring that picture out from its hiding-place. First, you must have a shallow pan at hand, and place yourself near a good supply of water. Into the pan you pour the chemicals previously mixed, necessary for the development or bringing out of the hidden image. These chemicals are, oxalate of potash and protosulphate of iron. To simplify matters, the inventor of the tourograph puts up these chemicals in papers, so that you only have to put into four ounces, or a gill, of water[D] one paper of the potash and another of iron; mix well, and the solution is ready for the plate. This must be placed in the tray with the film side up, and the solution flowed over it. When completely covered, let it remain, and carefully watch the development.

This is the period of greatest anxiety for the young operator, for it is the critical stage of the proceedings. A few seconds will determine whether you have a picture before you, or merely a square of plain glass. Gradually the details unfold themselves: the “high lights” or white portions first, then the “half tones” or grades of shadow, then the deeper shades of foliage or objects feebly lighted. When the view has come out distinct, seems to progress no farther and to gradually fade away to a deep brown, you have got out all it is possible to obtain from that exposure, and the plate must be removed from the solution, and chemical action arrested by washing in clear water.

Now you have before you tangible evidence of success, but your picture is not complete; it is dull, perhaps obscure, and if exposed to the light of day would quickly vanish. It must now fixed in another solution and in another dish. The “fixing solution” is made by dissolving half an ounce of hyposulphite of soda in five or six ounces of water. Into this place the developed plate, and allow it to remain until all the whitish film is dissolved away. If both operations are faithfully performed you will have, on taking the plate from the solution and holding it to the light, a brilliant picture on glass—the negative—with all the lights and shadows reversed, the white portions quite opaque, and the dark parts almost transparent.

Now wash very thoroughly in clear water, beneath a tap if possible, or by pouring a gentle stream over the glass for a few minutes, in order to remove every trace of superfluous chemical substance that might work injury. As a precaution against the possible peeling of the film, it is well to dip the negative in a strong solution of alum and water, then wash again, and set up to dry in a slanting position, with the film side next the wall. When perfectly dry a coat of photographic varnish, furnished with the chemicals, is flowed over the coated side of the glass, and the impression is securely fixed, ready for use in printing. Having secured the negative, your object is virtually attained: the possession of a souvenir of a vacation ramble, a favorite view, or of a picturesque camping-place. If it were my negative, I should take it to some good photographer, and let him prepare from it the prints I wanted, as that expense is small, and involves a good deal of labor for the amateur. But I suppose my readers will wish—as I did years ago—to see the whole process, and to make their own prints or paper pictures.

PRINTING FROM THE NEGATIVE.

White paper coated with albumen is made sensitive to light by being floated upon a solution of chloride of silver in water; and this, when dry, is placed against the negative and exposed to the sun. In this way, by pressing the silvered surface of the paper against the film side of the negative, a duplicate impression of the picture on the glass is transferred to the paper. This may be repeated with other pieces of paper any number of times, until hundreds are obtained from the same negative. Instead of attempting to prepare the paper yourself, it would be better to purchase it already sensitized, which you can do of any dealer in photographic goods. A printing-frame, or grooved block with a spring back, is used in printing. After having placed it with the negative and paper in the sun, watch carefully. By removing the frame and retiring to a dark corner, you can examine the paper by unspringing one-half the back at a time, and thus print to the degree desired. It is best to print a little darker than it is designed to have the print when finished, as it will bleach a little in the subsequent process of toning. This toning operation, as well as the cutting up of the paper, the placing of it on the negative and removing it, should be performed in a darkened room. When a sufficient number of prints are done, trim them the size they are to be when finished, wash in two or three changes of water, and then place in the “toning bath,” made as follows: Chloride of gold one grain, water ten ounces, saturated solution of bread soda three or four drops. This will change them to a deep bluish or purple color, and gives them that lovely tint we admire in fine photographs.