van Monckhoven, Désiré van. A Popular Treatise on Photography. Translated By W.H. Thornthwaite. London, 1863.

Chapter VIII.
On the Glass Room in which the Sitter is Placed and the Rules to be Observed in Taking Portrait and Landscapes

To take an artistic portrait, or to choose the most favour able point of view for a landscape, requires an artistic taste not to be acquired by reading, but allied in its character to a natural instinct, of which instruction only develops the germ, while practice simply modifies any perfects the details. The remarks on the subject-matte of this chapter will therefore be of an essentially practical nature.

The general detail and arrangement of an operating room suitable for photographic purposes, is represented in the cut on succeeding page. It should be in some elevated position, either on the roof of the house or on platform specially erected for the purpose. The side next the south should be entirely closed, whilst the other towards the north, is glazed. The sheets of glass employed should be of moderate thickness, as a protection from storms of hail, &c., and as white as possible-rather o a bluish tint than approaching at all to a green or yellow colour. It is of importance to attend to the colour of the glass used for the operating room., for, should it be of a green or yellow tint, a considerable amount of actinic rays*****

The glass rooms should be furnished with curtain; having cords attached to them, by means of which the too energetic action of the light play be moderated, and proper direction given. to it. In the figure it will be seen that three sets of squares are shown-the upper one (of ground glass), which is parallel with the floor or ceiling; the lower one, which replaces the wall; and the middle one, which is on the slope.

Fig. 55. The Glass, or Operating Room.

If now, with the object of producing an artistic effect, it be desired to inundate the front, of the model or sitter with light, the lower and middle set of curtains should be snore or less closed. If a lateral lighting be desired, the curtains of the upper window should, on the contrary, be closed. The good taste of the operator must, however, guide him as to the best disposition of the light.

On the right of the engraving, Fig. 55, is represented the shaft of a column, against which the model may lean; also a balustrade, with a landscape painted in distemper; and near the middle a white marble chimney-piece of the style of Louis XV.; all of which accessories, or others of a similar character, will be found to aid in imparting a general appearance of elegance to the resulting picture.

The colour of the walls exercises a marked influence on the result. They should not be painted either red, yellow, or green, for these colours have a very weak photographic action, and throwing around them, as they do, tints of their own colour, tend to prolong very materially the time of exposure. Violet and blue colours are preferable, but as they produce whites in the print, and as a wall painted either deep blue or violet produces a result exactly similar to a white wall, they should not be used for the background, or that portion behind the sitter. Bluish grey is a mixed tint which, on the whole, yields the best results, and is a colour with which the whole of the glass room may be painted, except that, according to taste, some parts may be more or less deep than others.

It will be found very convenient to have several moveable backgrounds, each painted with a different depth of colour, so as to be used according to the colour of the dress, &c., of the sitter, and thus produce the most effective contrast.

Oil colour is very disagreeable on account of its reflection. It will be found best to employ a mixture of slaked lime, litmus, and lamp-black with which the whole. of the room may be painted, simply varying the proportion of black. The same colour will serve to paint the floor of the room; but if a carpet be employed instead of paint, it is equally important that it should be of a greyish tint.

In reference to the best colour for dresses to be worn by sitters, the same remarks apply as have been made respecting that of the glass room; that is to say-neutral tints, analogous to grey, violet, and blue, come out well, while red, yellow, and green, yield results of an opposite character. By increasing the exposure, however, in some cases, and diminishing it in others, the undue predominance of any particular tint can be materially diminished.

When one or more persons are to be taken, they should be allowed, in the first place, to assume an easy, natural position, and then, by placing behind each a head-rest, in such a way as to retain them in the position chosen, the required steadiness of the upper portion of the body is secured.

It is not necessary that the sitter should press the head too strongly against the head-rest, but on the contrary, it should only lightly touch; because too great a pressure restrains the respiration, thus imparting to the sitter an appearance of constraint and uneasiness.

There are two kinds of head-rests. One in iron, or of iron and wood, is represented in Fig. 55. The lower part consists of a tripod and tube of brass weighing about 40 lbs., which serves to prevent vibration in the upper portion, which is applied to the head. This consists of an iron tube having one piece forked, and capable of being adjusted and fixed by a screw in any desired position.

Fig. 56 Head-rest.

These head-rests are made to stand on the ground; but Fig. 56 shows one constructed so as to be attached to a chair.

This form of head-rest is generally made of hard wood:--e is a flat piece of wood, to be adapted to the back of a chair; two clamping screws, f f, are attached to it; i i a grooved board which comes behind the chair. It may be easily raised and depressed, and is fixed in any desired position by turning the screws f f. b b, a double-jointed piece for adapting to the position of the head, and capable of being fixed by means of the screws shown in the figure. The whole of this piece may be raised and lowered, and fixed at d. a is a moveable forked piece, against which the sitter leans. It will be easily perceived that the back of the chair must come between the pieces e and i i.

Figure 55 shows also the manner of obtaining a focus, in connection with which may be observed that too great an inclination should never be given to the camera; as a rule it is best to have the lens about the height of the chest. A very slight inclination of the camera will then be sufficient to get a correct, image of the sitter from head to foot.

In taking a portrait from a sitting position, it is best to lower the camera-stand a little, and thus avoid too great distortion.

The nearer the camera is brought to the sitter the longer the exposure; and inversely, the further the camera is removed, the shorter the exposure. And it is in this way that the time of exposure may be varied from one second to three hundred. But as a general rule, in taking a full-length figure in summer, the plate should be exposed twenty seconds, while a sitting position will require thirty seconds. In winter these times of exposure should be increased one-half.

The following is a general summary of the operations involved in taking a portrait. The direction and amount of light are the first 'things which claim attention, then the attitude of the sitter. Focussing is the next operation, during which the sitter should be requested to keep still, though not maintaining perfect immobility. The plate should now be prepared in the dark room, on returning from which any alteration which may have taken place in the pose of the sitter during the absence of the operator is corrected, and efforts made, by cheerful conversation, to induce an agreeable expression. Then. when everything seems in order and ready, a final and rapid adjustment of the focus is made; the focussing-glass is withdrawn and replaced by the camera-back, containing the sensitive plate. The lens is now uncovered and the plate exposed, the necessity of complete stillness having been previously enjoined on the sitter, explaining, however, at the same time, that he may breathe in the ordinary way, and if necessary wink, but not move his eyes from the spot where first directed. The time of exposure having expired, the lens is covered and the slide of the camera-back closed, and the development proceeded with in the dark room.

With reference to the means to be employed to estimate the time of exposure in seconds, it will be found best to read the time from a good watch with a second-hand, though the same object may be attained by suspending a leaden or wooden ball by means of a cord 39 1/5 inches long. If the pendulum so constructed be made to oscillate, it will be found to mark seconds of time with sufficient accuracy.

It has been already mentioned in chapter seven, that lenses of a different construction are necessary for landscapes from those which are used for portraits. For views and architectural subjects a single achromatic lens is sufficient, but for portraits a double combination is necessary. It has also been stated that the form of camera-stand, Fig. 46, and cameras, Figs. 47 and 48, are those most applicable for landscape photography.

The rules which can be given for taking views are much more simple than those for portraits. In point of fact, success depends mainly on the taste of the operator in selecting the landscape which he desires to reproduce, and the particular point of view from which it is seen. The focussing is accomplished in the ordinary manner.

It is only necessary to add, that views are taken by the wet as well as the dry collodion process: With the latter all that is required is a grooved plate-box, containing some prepared plates, a camera-stand, and a large black cloth with which to cover the legs of the camera-stand, when it becomes necessary to replace an exposed plate by one which has not received the luminous impression. With the wet collodion process, a photographic tent, or a light tent carriage, is indispensable; and the operator must also take with him all the paraphernalia of dishes, baths, bottles, &c., which form the necessary furniture of a dark room.

Notwithstanding these difficulties, the wet. collodion process is to be preferred for the reproduction of architectural subjects and landscapes near great cities. But for a long voyage, the dry collodion process is certainly the best.

In the wet collodion process, the nature of the result (good or bad) is known at once on the ground; while with dry plates the character of the picture is not ascertained until the development is effected, which almost invariably takes place at a great distance from the locality in which the view was taken.

In large cities and flat countries it is very easy to have a tent or light carriage of waterproof cloth, carried, or drawn if need be, by a porter or guide-an arrangement which offers the advantage of allowing the operator to stop wherever he pleases, and conduct the work with great facility.

Fig. 57. Iconometer.

Generally, before taking views, a preliminary visit is made, with the object of ascertaining the best points of view, and on such occasions the iconometer, or view meter, Fig. 57, is found very convenient. It requires to be expressly constructed for each focus of lens and size of camera, and resembles very much in appearance an opera-glass. It consists of a small lens, a camera, of the shape of an opera-glass, and a square focussing glass. By turning the lens towards the view it is represented reversed on the ground glass; and in this way the operator can judge whether his large camera will take in the whole or what portion of the required view.

Instead of the iconometer with lens and ground glass, a more simple one may be employed, which in many respects, however, is similar to that indicated in Fig. 57. The observation is made through the front opening, and on the large circle behind (to the left in the figure) a rectangle is described equal to that which is yielded by the lens attached to the camera. It is then only necessary to observe what objects are included in the field of vision, in order to ascertain what will be reproduced on the ground glass. The iconometer with lenses is, however, the most convenient for general use, as it affords an opportunity of knowing whether in the case of taking an architectural subject, for example, the operator is or is not too close, for then the vertical lines incline towards a point, like the furrows in a horizontal field.