The Postcard Lantern As An Aid To Copying And Enlarging.

A postcard lantern or its equivalent, for a simple substitute is quite easily devised, will often prove of use to the photographer for special work. It may be of great assistance, for example, when one desires to make a copy or an enlarged negative from a print, while at the same time introducing modifications, or blocking out unwanted portions.
Direct enlarging with a postcard lantern is not new, having in fact been suggested by A. E. Swoyer, in the "American Annual of Photography" for 1914. That writer, however, regarded the projected image as an end, whereas in the present article it is simply a means to an end or intermediate stage, while the method adopted is entirely distinct.
It will be seen, by reference to fig. 1, that the postcard lantern consists of a body, A, in the front of which is fitted the objective, B, while at the back is a hinged door, C, with grooves to hold the print, or sometimes a sliding carrier. A good source of illumination is two 30 c. p. or SO c. p. metal filament bulbs, D and E. The inside of the body U whitened, and it will be noted that the ides nearest the lamps are at such an angle as to reflect the light on the print. Two small interposed screens, or some similar arrangement, prevent direct rays reaching the lens. Cowled chimneys are usually fitted over the lamps, and due provision made for ventilation.

The most important item is the lens, which should be of fairly large aperture, owing to the loss of light by reflection, and should have a flat field. Cheap postcard lanterns often have objectives with so round a field that the holder has to be curved to get uniform definition. Such a lens is, of course, quite unsuitable for copying or enlarging. Many of these objectives are not even achromatic, and, on the whole, a proper photographic lens is Bach to be preferred, even to the best of them. The lens must be capable of covering a plate at least as large as the print to be projected and the lantern should have sufficient focal adjustment or extension to render a fairly small picture possible when required.
There will be needed, in addition to the lantern, an easel of the type shown in fig. 2. This consists of a frame, A, containing a

wheat of plain glaze, B, and supported in a vertical position by a firm base and struts. To the frame A, is hinged a smaller frame, C, which, when closed and secured by a turn button, presses on the glass.
The print to be copied is inserted at the back of the lantern, and focused sharply to the desired size, on a sheet of tracing paper stretched taut between the two frames on the easel; or, if preferred, a piece of finely ground glass may be placed in the frame, A, instead of a plain piece, and the tracing paper dispensed with. If the second coarse is adopted, the ground aids) of the glass should be at the back of the easel.
The worker, standing or sitting behind the easel, now has it is power to modify the projected image considerably, by of pencil or stomp work on the ground glass or tracing and even the brash may be employed advantageously in cases. Since the image is a positive, there is no difficulty in exactly how the final result will appear. Cars, of course, have to be taken that the work matches the colour of the image.
The next step is to make a negative from the modified image, by setting up a camera, F (fig. 1), behind, and central to the easel, O, without moving or interfering with the lantern. Thus, the copy negative will contain all the introduced work as well as the essential characteristics of the original, and the result if all is well done, will be a considerable improvement. The negative may obviously be any required size, though preferably it should be smaller than the projected image, as this reduces the likelihood of grain showing.
It will be seen that this method affords a handy way of inserting a black background, by painting round the projected image with any suitable opaque; or of introducing accessories on an originally plain tight background; copying joined up prints an I combinations; adding skies to landscapes; and many other purposes.
One may also make enlarged modified negatives direct from prints, by working-op the projected image, as before described and then, having find covered the objective, placing a large plate in the frame behind the grand glass or tracing paper, the exposure being then given by uncovering the objective for an estimated time. In this case, the postcard lantern must evidently be light-trapped properly, which is not so necessary for copying with a camera; while a little extra space mast be left in the rebate of the easel frame to allow the insertion of the plate. Enlarging in this way softens the definition a little, and thus lends itself to artistic elects. There may also be an alight grain, bat with proper cars this should not be objectionable. Backed plates should invariably be used.
Since metal-filament lamps do not give out much heat, it in traits feasible, with an intelligent study of size and ventilation, to hint a simple wooden, lantern of the kind under discussion; or, with but a little adaptation, one or other of the various contrivances for ^Urging by reflected light without a condenser may be pressed into service.
To anticipate difficulties which may, perhaps, perplex some who are unfamiliar with postcard lanterns, it should be stated that the projected image is always laterally reversed. Viewed from the rear of the easel, however, there is no inversion, when explains why copying is done from the back, that also I fortunately the most convenient position.
A. LOCKETT.

Fog In The Studio.

           IN many localities, notably in the London district, the state of the atmosphere has left much to be desired from the photographer's point of view. Not only has there been an actual deficiency of light through the presence of more or less yellow fogs, but there has been great difficulty in securing brilliant negatives on days when the light was fairly good, because of the general haziness of the atmosphere. Many photographers suffer from this fogginess without quite being aware of the actual cause of it. A simple experiment which will show in a rough way how much fog is present in any room at various distances can be made with the aid of two ordinary black velvet focusing cloths, velvet being chosen because it has leas reflecting power than any other material in ordinary use. One piece of velvet is crumpled up so that some parts produce deep shadow and put on a table in the position usually occupied by the sitter. The operator then stands by the camera at the distance at which a full-length portrait would be taken, and holds up the other about a foot from his eyes so that it half covers the piece on the table. If there is any appreciable amount of haze present he will find that the deep shadows on the distant piece appear quite grey in comparison with those on the piece which he is holding, and at once finds an explanation of the flat negatives which he has been obtaining.
           Having established the existence of the fog, our aim is now to minimise its effects, and there are many methods by which this end may be partially attained which, when put together, result in a substantial improvement in the quality of the negatives. In the first place, the studio windows should be kept clean, so that as small an area of glass as will give the desired lighting will be needed to obtain short exposures. By thus closing out all unnecessary light we reduce the general illumination of the fog and get a much brighter image. This can perhaps better be seen when working with artificial light. If we build the lamps in with screens or backgrounds so that the light falls upon the sitter only and none reaches any other part of the studio, there are only three or four feet of fog to work through, while if the whole of the studio is illuminated the amount is greatly increased.
           In foggy weather the lighting of the sitter may be more concentrated than is usually necessary, as a more vigorous negative will then be obtained, and printing can be carried on until the shadows are of sufficient depth. Windows become coated with smoke in a day or two in the winter and act as undesirable diffusers, so that it is advisable to clean at least the panes which it is intended to leave unscreened.
           A fairly warm temperature and good ventilation tend to reduce fog and to clear it away quickly. We have often noticed that a room or studio has remained foggy long after it has become fairly clear outside. When the necessary power is available, an electric fan will do much to establish a current of air, which should be directed towards an open window or door. A proper exhaust fan fitted near the roof is the best form, but the portable ones are of considerable value.
           We have already pointed out how the effect of fog may be reduced by cutting out all unnecessary illumination. A further improvement may be made by using a lens of as short a focal length as possible, though not so short as to introduce distortion. Where sufficient length of studio is available, it is now common to use sixteen or eighteen-inch lenses for all-round cabinet work, and it is quite good practice in clear weather. But at other times a tea or twelve-inch lens will be found to give much brighter pictures. As a matter of fact, many photographers have found this out without knowing the reason, and attributed the improvement in brilliancy to some other property in the lens than its focal length. Whatever lens is being used, it should be kept clean. Lenses will get as dirty as windows do in a smoky atmosphere, and will then yield flat images in the clearest light. If a lens has not been kept clean it is interesting to take a negative with it before cleaning and one directly afterwards. In most cases the contrast will be striking. Lenses should be cleaned carefully, a vigorous rob with the corner of the focussing cloth is not to be recommended, as such treatment soon "greys" the surface. An old worn handker-chief, kept in a box free from dost and grit, should be used. If there is a greasy deposit from town smoke, a single drop of pure alcohol may be applied on a tuft of cotton wool, and then the surface quickly polished with the handkerchief.
           Although we are opposed to all “tinkering” methods of development, the judicious use of bromide upon exposures which have been made under adverse conditions is quite permissible. To describe the action of bromide in popular language, we may say that, when used upon an over-exposed or foggily lighted plate, it allows the high-lights to get a start before the shadows begin to develop. If the plate be developed right out this advantage is lost, but as most portrait negatives do not reach this stage there is a decided benefit to be obtained by the use of bromide in the cases we have mentioned. It is necessary to add the bromide to the developer before immersing the plate. Once development has started it is of little, if any, effect. The character of the plates used should also be taken into consideration. Some brands tend to give brighter results than others. These should be chosen for foggy weather, as, although the scale of tones may not be so long, the resulting print is more satisfactory.

Practicus In The Studio: The Camera and Lens.

           The selection of the studio camera and lens, or rather lenses, for it is a serious handicap to have to work with one only, deserves the most careful consideration, and in comparison with other items a liberal allotment should be made when planning your outlay. A badly made camera or an inferior lens will soon cause the loss of more money than is saved on their cost, and will do much to brand the work turned out as second class or worse. The operator should never work with the feeling that he could do better if he had better apparatus. Now I do rot want to convey the idea that such apparatus should necessarily be costly, and as an instance of this I may say that I recently selected for a young friend a 12x10 outfit, comprising camera, studio stand, a 12 in. f/4 portrait lens, and a 5 D. Dallmeyer f/6, at a total cost of less than 25, all being purchased from well-known London dealers.
           Broadly speaking, there are two models of studio camera: the British pattern, as made by Hare, Watson, and several other makers, and the German model, which has been extensively copied by English makers. For practical purposes there is little to choose between them. When choosing a camera it is desirable to have one which is not permanently built into its stand, as in the case of any accident to the latter the whole outfit is rendered useless; besides this, it is impossible to get the camera near the floor, which is often necessary when taking children's portraits.
           Movements’ essential to the studio camera are rack and pinion or screw focusing. Personally I prefer the latter, although it is considered rather out of date now, as it never gives trouble by becoming loose and allowing the back to move, besides being conveniently placed in a fixed position. There should be vertical and side wings to the back and a rising front; the bellows should be of ample length, bearing in mind that lenses of much greater focal length are now used than was formerly the case. Twenty-four inches is not an uncommon length, so that for a 4*(1/2)-in. head on a 12 x 10 plate we require an extension of 36 ins. This should not be lost sight of if one is offered an otherwise suitable camera of old pattern, although the defect may be remedied by fitting a cone extension or "box front." Whatever camera is selected it should be well cared for and not allowed to become covered with the black greasy patches one too often sees. In passing I may remark that ordinary spirits of turpentine is an excellent medium for cleaning dirty woodwork, and an hour's work with it, followed by some good furniture cream, will often make a camera and stand look worth 50 per cent, more than when you started.
           It is very usual to fix repeating backs so that two half- or quarter-plates can be used side by side. This is a survival of wet plate days, when it was no more trouble to coat and sensitize a whole-plate than one-half or quarter the size. I think that the American plan of "one slide, one exposure" much more handy and safe. Many of the American studio stands have racks on either side, one for unexposed and the other for exposed, a dozen or more cheap single slides each for a 7 x 5 (American half-plate) being supplied with the camera. Double exposures can then only be made by the grossest carelessness. Another "Yankee notion" which is a good one is to make the pushing of the slide into the exposing position open the shutter. This has been improved upon by Messrs. Dallmeyer, who introduced a back in which double flap exposing shutter slipped along with the slide, so that the lens did not require covering before the slide was opened; this saves much time. In my opinion, any camera-maker who would supply such a device fitted with a number of cheap slides would find his reward. Think of the convenience of being able to make a couple of dozen exposures without having to refill.
           If the ordinary stands do not seem satisfactory to you, the platform style, of which the Hana and the Semi-Centennial are the best known examples, will probably meet all requirements. In these a Platform carrying the camera travels between two uprights, and the camera may be placed as high as an ordinary person can see to focus at or lowered to a few inches from the floor, the castors should be rubber-shod, and, if possible, a brake fitted, so that there is no risk of moving the camera when inserting the slide. The lens shutter is an important feature in studio apparatus, and the rubber fittings thereof have probably conduced to more profanity than all the rest of the outfit. I like the feel of a ball and tube while it is in good condition, but that is usually only for a brief period before it begins playing tricks before an important sitter. The Bowden wire cable or "Antinous" release is much move reliable, and would be better if the bicycle cable were used instead of the weaker form- usually fitted. The pressure button, too, is particularly annoying, as one cannot grab it anyhow as one can the rubber bulb, but must get hold of it just right between the fingers. It would .be quite easy to make a pear-shaped handle to work like the rubber one, and if the makers want a sketch for it I will send them one, but that will probably not be till the patent has expired.
           Now for the shutter itself, after having relieved my feelings about releases. The best shutter I have ever used, and I think I have worked with nearly every pattern, is an American one, the Packard Ideal There are several shutters, none British, of this pattern, which are probably nearly if not quite as good. It is made on the sector principle, with vulcanite leaves, and the working parts are balanced, so that very little pressure is required to actuate it. Let me confess it works best with a rubber ball and tube, the only disadvantage of which is that the rubber is too hard and the ball splits; still, if you substitute a good English bulb this trouble vanishes. The next best shutter is the velvet flap, originally introduced by Mr. James Cadett and still in use in the majority of studios under the name of the Guerry shutter. Why an English shutter had to be made in France and sold under a French name I cannot say, but so it is. The hemispherical bellows, or Grundner's shutter, is fairly satisfactory, but the interior bellows is troublesome. With the Antinous release it is much better, although the leather bellows which forms the shutter is easily injured by a. careless operator; still, on the whole, it is a good shutter.
           No less important than the camera is the lens; in fact, although with a faulty camera and a good lens we may produce excellent results, it is impossible to reverse the conditions and do so with a faulty lens upon the finest camera. The requirements of different studios vary so greatly that it is difficult to suggest the most suitable all-round selection. The length of the studio is an important factor, and I feel that I cannot do 'better than to refer the reader to the table dealing with the subject in the B.J. Almanac. Next in importance is the type of lens. Of late years there has been a growing tendency to oust the time-honoured Petzval or Dallmeyer types in favour of the rapid anastigmats. There are two sides to the question, and these have been little discussed. The anastigmat is unquestionably far superior to the portrait lens, when tried to its fullest extent, but it loses this position when only a small portion of its field is being utilized, as its cost is much greater and its qualities are wasted. If I were selecting lenses for a short studio, say, an eight-inch for cabinets and a twelve-inch for whole-plate standing figures, my choice would be an f/4.5 anastigmat of the desired focus, but if I could use a fourteen or sixteen-inch lens for cabinets I think that I should go for a portrait lens, which I could get at much less cost and which would possibly be fitted with a "diffusion of focus" adjustment. One point which I would specially impress upon the purchaser is to choose as long focus a lens as his studio will accommodate for the greater part of the work to be done. If the studio be very short, so that a 6*(1/2) or 7-inch lens has to be used for full-length cabinets, it is better to obtain at least a ten-inch lens for heads and half-lengths and to get a smaller lens for the full lengths. There are now some very cheap Anastigmats which work well, with apertures of f/6 to f/7.7, to be purchased at prices which were formerly charged for common foreign rectilinears, and these will answer for short-focus portrait work.
           There is a growing demand for soft definition in portraiture. By this I do not mean absolute fuzziness such as some selecting committees used to revel in, but a general softening of outline and suppression of small detail without loss of texture. To secure this many lenses have been introduced, and I have made negatives with most of them. The majority give too great an amount of diffusion at full aperture, and when stopped clown to reduce this exposures are unduly prolonged. For the everyday professional who wishes to make an essay in this direction I would suggest the use of the "patent" portrait lens of Dallmeyer, the recent portrait lenses of Ross, and the Cooke portrait lens. All these have adjustments which allow of any degree of diffusion up to a certain point being introduced at will, while in the case of the Ross and Dallmeyer lens a further stage may be attained by removing the back combination and using the front lens per se and in situ. There are many nameless portrait lenses, very bad as a whole, which would make excellent soft focus lenses if the back combination were taken out and lost. It should be remembered that the front lens of a portrait lens usually requires only slightly more than double the exposure of the complete lens, and not four times, as is the case with a rectilinear. The focusing eye-piece or magnifier is a very useful little adjunct to the camera outfit, as it saves eye strain and makes for certainty in focusing, especially in copying. One of fairly good quality of the Ramsden pattern will be found most satisfactory, as the field is flat and the definition good. The cheap forms with single lenses have too much spherical and chromatic aberration to be used by anyone not skilled in optical observation, and those who are would not give them house room.

PRACTICUS.