Amateur Photographer & Cinematographer (1936)

November 4th, 1936 iHi AMATEUR PHOTOORAPHER | ta 6 CIHEMATOORAPHER o I Readers’ Rints, Tips and Gadgets AN ENLARGING TIME-SAVER. PROBABLY seventy-five per cent of the enlargements turned out by most amateurs are made on the smaller sizes of paper of about postcard or half-plate size. A great deal of time is wasted in pinning these small sheets to the easel, and each print must afterwards be trimmed to remove the holes made by the pins. The simple holder de¬ scribed here will obviate these troubles and at the same time it has several other advantages. The holder embodies a mask which gives the prints a white margin all round, minimising waste and ensuring a neat linish. It can be moved instantly to any position on the easel so that any desired part of the picture can be selected for enlarging. This is a great advantage and avoids the need for rulings on the easel. Such rulings are of little use with the simpler types of enlarger where the negative carrier is not provided with centring adjustments. It will be seen from the drawings that the holder is made from three pieces of cardboard glued together and fitted with pins at each corner. The back is best made from a thick piece of mounting board with a smooth white surface, so that it can be used for focussing upon. It should be about \ in. larger all round than the enlarging paper or postcard. A suitable size for postcards would be 6^X4^ in. The distance-piece which holds the cards in position should be the same size as the back, and about twice as thick as a postcard. It must be cut away to a U-shape as shown in the drawings. The exact size of the part to be cut away can be got by tracing round a postcard (or other size of enlarging paper). The margin at the foot can be about | in., and around the sides about J in. Any piece of good smooth card can be used for the mask. It should be the same width as the other pieces, and about § in. shorter. A rectangle is cut away from the centre, leaving a sufficient margin all round to give the prints a white border of I to J in. in width. The top margin of the mask should be about ^ in. in width and arranged to allow the prints to project about ^ in., so that they can be easily withdrawn. After gluing the three pieces together push-pins are inserted at each corner and glued in position, leaving the points pro¬ jecting about ^ in. at the back. This allows the holder to be fixed in any position by merely pressing it against the easel. A neat finish can be given by painting the mask black. This also allows one to see at a glance the exact size of the printing paper. A. Harcus Cutt. AUTOMATIC'' ENLARGER FOCUSSING. The following notes and diagram will show how a vertical enlarger of the type illustrated can be readily made almost self-focussing, with little more trouble than that occasioned by an hour’s careful measurement. The enlarger described is focussed by raising the lantern (A) bodily, a clamp being provided for fixing it to the vertical support at the back, and then turning the knob (B) until the image of the illuminated negative is sharply defined on the baseboard. If an old negative with fine lines ruled on it, one or two inches apart, is used in the carrier, it will be a simple matter to decide the correct positions of the lantern and lens panel necessary to give any specific degree of enlai'gement. If then a pointer is fixed to a suitable place on the lantern or its carriage, and a scale of magnifications is engraved on the vertical support as shown, the correct position for the lantern for any required magnification may afterwards be easily found. To obtain the corresponding lens setting, a strip of metal or wood is cut so that when the lens panel is resting on the strip (C) as shown, the image is sharply focussed. The strip is clearly marked with the degree of magnification for which it is to be used, and is slid out of position before printing is started. It is advisable to arrange that the pointer on the lantern shall run as close as possible to the scale to avoid error due to parallax, and it is essential that the same negative carrier shall be used as was employed to calibrate the instrument. Since woodwork is unfor c tunately influenced to some extent by the weather, it is as well to check the set¬ tings periodically, but no great trouble need be anticipated. No claims are made that a precision enlarger may be obtained by the above method, but certainly considerable fatigue may be avoided in the dark-room by using such a device for focussing. M. L. Haselgrove. FILM CLIPS. ET prints, and even more wet films, are so slippery that they are very liable to slip out of wooden clips. This can be prevented by inserting a gramophone needle in the jaws of the clip in the way shown in the drawing. The usual needle is rather too long, and must be broken in half. This is done by gripping half the needle in a vice, and tapping the projecting portion with a hammer, when it will break off close to the vice. The shortened needle is then pushed, point outwards, into a small hole drilled in the clip. A. Loveygrove. 451 9