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the side of it an arm moves on a graduated scale and can be set in a moment.
Quick exposures are given by means of a Kershaw shutter, which is set by pulling one silk cord and released by giving a little pull on another, both of which are situated at the front of the instrument.
For time exposures it is requisite to open the front as in fig. 2, and expose by means of a cap. The rectilinear lens is provided with diaphragms with apertures (fig. 8, 10, 13, 16, 22, and 32).
The apparatus is very compact, measures barely 10 by 54 by 44-ins. and is covered in Morocco. Mr. E. V. Swinden, 14, Westminster Chambers, 38, Crosshall Street, Liverpool, the inventor and manufacturer is certainly to be congratulated on introducing such a small, neat, and efficient camera as the one above mentioned.
ConsIDERABLE has been written on this subject, but from the numerous inquiries it would appear that either the articles failed to touch on some important point with sufficient clearness, or something necessary had been omitted. There is nothing difficult in the production of slides (says Mr. H, 8, Nutt in Anthony's Bulletin), and with a little care and use of brains very good ones could be made, with few losses. The plates on which they are made being supplied all ready for printing, either by contact or through the camera, have relieved the amateur of many of the troubles that surrounded him in the old wet-plate days, when it was a necessity to prepare the bath, developer and intensifier, and have them in perfect order. A streak, comet, or some other of the many imperfections that were constantly showing themselves, have been done away with, and in place we have a neat parcel containing twelve plates on fine thin glass, cut to proper size, ready for use, and at will. These plates, being what are termed ‘ slow dry plates,” can be handled in much stronger light than the more sensitive landscape plates; hence, in printing by contact, sufficient non-actinic light can be used to adjust the plate on the negative, so that the picture will occupy the desired position. The handiest light to use for printing I have found to be one of the patent gas jets, which is apparently extinguished when the gas is turned off, but is actually lighted in a small tube below the regular jet, and enclosed in a case surrounding the burner. On turning the tap, the small jet lights the regular burner.
The Optical Magic Lantern Journal and Photographic Enlarger.
The time of exposure requires practice and judgment. MHoiding the printing frame about 15-ins. from the burner, I give from five to ten seconds, depending upon the strength of the negative and its colour. If desired to show more on the slide than a contact print will yield, the entire negative can be printed in the same space as occupied by the opening of the mat, by copying it through the camera. As these cameras are sold and advertised by your publishers, I will not describe it here further than to say it is a double camera, one in which the lens goes in the centre compartment, the negative on one end, and the lantern-slide plate on the other, the size of subject shown on the plate being determined by the position of the lens. When using 4 x 5 negatives, the 4 x 5 camera will be found more convenient, and, when once set in position, all the negatives can be copied without changing the position of lens or plate. An extra holder is advisable, for, when one picture is printed, a new negative and plate can be exposing while the previous one is developing. I use a lens with minute diaphragm that will require at least three and a half minutes’ exposure. This gives me time to put the last exposure in the tray, and look at those being developed, and to move finished ones from the hypo, etc.
The camera should be pointed at the sky without anything intervening. If this is not practical, put a clean, smooth piece of tissue paper in the window, and point the camera at it, with fully two feet space between the negative and the paper. If placed too close, there is danger of photographing the grain of the paper through the clear parts in the negative.
For developer I find that a weak one is necessary, and use the same kind as for developing the negative, adding an equal bulk of water and from one to two drops of a saturated solution of bromide of potassium. The development must be carried until the image appears much denser and stronger than wanted in the finished slide. It will thin out wonderfully in the hypo soda. This latter must be clean, and I never use an old fixing bath. I add three ounces hypo to one pint of water, and to this one ounce of acid sulphite of soda. This latter is most useful in the hypo bath for negatives.
After the slides are properly fixed, they must be thoroughly washed. I emphasize the word thoroughly because if you value your slides and wish to keep them perfect, you must eliminate all the hypo. The acetate of lead bath, as . introduced years ago by the late Mr. H. T. Anthony, is the most effectual of all. After washing in two changes of water for fifteen