EX CATHEDRA: Complete Development; Colour of Second-hand Lenses; Camouflaging the Camera; Varnishing Negatives.

Complete Development

            The maxim which is rightly emphasized to makers of bromide prints, namely, to develop thoroughly, is one which even now, although it has been repeated over and over again, is largely disregarded. Neglect of it is one of the chief causes of unsatisfactory quality in sepia-toned prints, the results of toning an image which has been rapidly and, therefore, superficially developed being greatly inferior to those in which development has been carried more deeply into the film. One rule which has been given for the guidance of bromide printers is that the time of development should be at leant three minutes, and exposure adjusted accordingly in order that the print at the end of this period of development should not exhibit the effects of over-exposure. But papers and developers having their particular idiosyncrasies, perhaps a more usefully applied rule for discovering whether prints are receiving this "full" development is to immerse half of s print only in the developer, and after the expiration of, say, half a minute to allow the developer to act upon the whole. If, then, development can be continued so as to yield a satisfactory print which does not show a difference between the two halves, the worker may be satisfied that his development u of the required fullness. On the other hand, a difference between the two halves will indicate that exposure can be advantageously cut down.

Colour of Second-hand Lenses.

            Those who are baying secondhand lenses will do well to give the question of colour some consideration. As is well known, long exposure to damp or atmospheric conditions lead to discolor the glass of the lens, or cause the balsam cementing the components to deteriorate with the same result. Some secondhand lenses that we have seen suffer from this very badly, the glass having quite a yellow tinge, in others, though existent, the defect is not so apparent, but if present the marked aperture of the instrument does not represent its actual working speed. We had one inch lens that when examined in a casual way showed little or nothing the matter, but when placed against a sheet of pure white writing paper a slight discoloration was at once noticed Slight though this was, it had a marked slowing action when using ordinary plates, though when orthochromatic emulsions were employed this to a large extent disappeared. Those having such instruments will do well to send them to one of the firms advertising in the advertisement columns of this Journal for repolishing or recementing of the glasses as the case may be, while if buying a secondhand instrument prospective buyers should be on the watch for a defect, which, though it might easily peas unnoticed, reduces the actual value of a lens very considerably. This discoloration is perhaps more frequently met with in the older instruments than in the modern anastigmats, unless these have been very much exposed to bad conditions, but it is a condition of things that all owners of good cemented anastigmats will do well to guard against.

Camouflaging the Camera.

            We commented recently upon the use of the small camera in certain branches of photographic work where its advantages may be turned to good account. A further instance of its value as a supplementary instrument in the studio was told to us the other day by a professional friend. He was commissioned to make a portrait of a child of whom previous experience had taught him that, however pleasing might be the expression on the little sitter's face, it instinctively froze directly the operator made a move towards the camera. The studio instrument was prepared in the usual way, and in front of it was placed a table with piles of books, etc., very carefully arranged to conceal a previously focussed vest-pocket camera, with its shutter set ready for an exposure. The usual attempts were made with the studio instrument and with small hope of obtaining a satisfactory picture. The operator turned away rather disgusted. Almost at once the little sitter was herself again, and casually, as it were, turning to the table the operator pressed down the shutter release of the vest-pocket camera, covering the action as if by taking up a book. As was expected, the exposures made with the studio camera were failures from the point of view of expression, but the small camera yielded a lifelike and pleasing portrait. The negative was carefully enlarged, and the result was an order for some dozens of prints. The idea of camouflaging a small camera should prove of value to those photographers who have to take portraits of nervy sitters, since the exposure may be made at a selected opportunity without the sitter being aware of it. Such a plan should help in overcoming many a difficulty in this respect. Though the negative is small, the quality can be of the best, and the resulting enlargements with a little working-up should give no indication whatever that they are not contact prints from large-sized original negatives.

Varnishing Negatives.

            Few photographers at the present time varnish their negatives, nor when ordinary bromide printing or enlarging is to be the medium is this course really necessary. But when a number of P.O.P. carbon or platinum prints are required from one negative, and the printing is done in the semi-open air for the most part, in damp weather it is a wise precaution to give the negatives a coat of ordinary cold varnish. Many present-day operators, however, find a great difficulty in getting an even coat of varnish over the entire plate by the ordinary method, and if this is not done there is a tendency for the varnish to dry in ridges, which means, of course, corresponding markings on the prints. Varnishing negatives by flowing the varnish on and tilting the plate at various angles until the whole is covered, and then draining the surplus back into the bottle, is an operation that requires a certain amount of skill, which can only be obtained with practice. We have for some time past varnished our negatives with an ordinary camel-hair (or hog-hair) brush. The exact kind is not very important, provided that it is well made and free from loose hairs. For this method, though not strictly orthodox, we may claim that it is comparatively easy to put a light but even coat of varnish on the film. None of the varnish need be got upon the back of the plate, and negatives may be very rapidly treated. Care should be taken not to get the brush too full of the varnish, or uneven coating may result. To those who have had no experience of varnishing negatives this alternative method may be recommended, although the essential feature of it is that a thin coating is rapidly applied.

EX CATHEDRA: Photographic Survey of London; The "Vest Pocket”; Non-photographic Side Lines; Vignetting Bromides; Drying Press Negatives.

Photographic Survey of London.

           The communication from the Camera Club, which we print upon another page, sets forth what is truly a very ambitions programme, no less than a comprehensive survey, in the form of photographs, of London at the present time. Until the opportunity ocean of learning, from the booklet which is shortly to appear, the contemplated organization of the undertaking it is clearly impossible to form an estimate even of its possibilities. But, at any rate, it may be thought that a scheme of which one first hears in March must call for an enormous and well-disciplined body of workers if it is to achieve its end of recording the face of London in the Peace year 1919. At the best of times it is difficult to stimulate an interest in the making of records which an to serve our descendants, and while we cannot too highly value the interest which the Camera Club is showing in this work, we are bound to think that some extraordinary army of photographers will need suddenly to be brought into existence if the aims of the promoters are to be realised.

The "Vest Pocket” Commercial Operators.

           There are occasions when a high-grade small camera, far from being a toy, may be of very real service to the photographer placed in exceptional circumstances. The fact that these instruments are fitted with lenses of short focus and wide aperture, and thus give good definition over many varied planes of distance without recourse to stopping down may often be of real service. A case in illustration of this point was told to us some time ago by a commercial worker. He was commissioned to make a series of pictures in a factory, which was rather poorly lighted, of certain pieces of machinery. A the work would have necessitated the use of a lens well stopped down in order to gain the required definition, and as the stoppage of the machinery was an important factor the operator took with him a vest-pocket camera. This he found rave all the definition required, and fine definition without stopping down the lens. The result was that the pictures were taken in a very short time, as the worker was enabled to use the lens working at f/6 instead o. one stopped down to f/22. Enlarged prints were made that gave the customer entire satisfaction. The same operator at a later period had to obtain a view of an old country house in the North of England for an estate agent, and the subject required could only be satisfactorily photographed from a narrow ledge of dill about a foot or eighteen inches wide. This was obviously impossible with the field camera, but, not to be beaten, the operator took his vest-pocket camera, carefully worked his way to the spot, and then, holding on to a bough with one hand, operated his camera with tie other, using the instrument at eye level. The result was a new and striking picture that had a material value in wiling the estate. Though, of course, not to be looked upon as a universal instrument, the modern vest-pocket camera fitted with a good anastigmat will often prove of very real value to the commercial operator when he is faced with difficult subjects. Provided care is given to obtaining a satisfactory negative there is no reason why, with a little working up, the resulting photographs should not be equal, and they may even be superior to contact prints from large negatives.

Non-photographic Side Lines.

           From one or two professional photographers during the past few days we have received letters asking for suggestions for other business, within the technical capacity of a studio establishment, which they might take up. While such enterprise has been undertaken, within our knowledge, by one or two photographers, it is difficult to make general suggestions, since very much will depend not only upon individual craftsmanship but upon the local demand for such articles of manufacture as may be produced. However, it may be worth while to mention the instance of a firm of Scottish photographers who have taken up, we believe with considerable success, the designing and making of toys, whilst in Kent is to be found a photographer who has specialised in the manufacture and design of fancy leather goods, such as calendars, and blotters, and whose work, as we have seen it at the British Industries Fair, possesses merit of a high order. It was first shown at the Fair of some two or three years ago, and as the exhibit is included also in this year's Fair it may be supposed that the project has turned out to be profitable.

Vignetting Bromides.

           Those who have cause to complain of the hardness of outline of bromide prints exposed in one or other of the customary machines may be glad of one or two hints which, if taken, will go a very great way towards removing a defect of this kind. One is to cut the vignetting card from the corrugated board sold for packing. If the 'board be cut so as to give a bevel edge to the opening, the corrugations will provide a series of serrations which make for softness in the print. The second hint is to interpose a sheet of fine ground-glass midway between the vignetting card and the negative. Most printing machines will allow of a frame being inserted between the vignetter and the negative, so that the glass can be introduced in the required position without adjustment, and as quickly removed; when unvignetted prints are required. The glass, of course, cuts down the light, but in these days when light of almost any power can be obtained from electric lamps this is a matter of small moment.

Drying Press Negatives.

           A method of quickly obtaining negatives in a condition for printing and enlarging, which is less known than it deserves to be is that discovered some seven or eight years ago by M.M. Lumiere. It consists simply in soaking the washed negative for about five minutes in a saturated solution of potassium carbonate. The effect of this treatment, quite contrarily from what might be expected, is to produce a temporary condition of hardness of the gelatine film, permitting of the negative being rubbed dry with a clean, dry cloth, after which it can be immediately printed from or enlarged. The readiness with which a negative is obtained in this state requires being the subject of trial before it be appreciated. On taking out of the carbonate solution the film seems to be covered with a film of grease, but very quickly polished with a cloth. We should not care to keep negatives in this condition if value is attached to them, for obviously, in the case of retention of such a hygroscopic salt as potassium carbonate, the film must remain moist, and such a condition is bound to aggravate any causes of impermanence which may arise from imperfect fixation. Moreover, we have come across plates which showed a tendency to strip from the glass under this treatment, and, therefore, on both accounts the negatives should be washed for a few minutes and dried in the usual way as soon as their immediate purpose has been fulfilled.