International photographer (Jan-Dec 1935)

Twenty-six The INTERNATIONAL PHOTOGRAPHER November, 1935 Flattening Prints MINIATURE CAMERA PHOTOGRAPHY A Bit of Advice ILATTENING PRINTS: The flattening of prints seems to be a major problem with many amateurs. If the photographer is still unsuccessful he can resort to one of the solutions for this purpose, which is obtainable from practically all dealers. These solutions merely reguire application to the prints to render them flat. However, there still is the guestion of how to obtain perfectly flat prints through ordinary methods. After the prints have been removed from the wash water, allow them to dry thoroughly. transmitted light. This is due to a small amount of alkaline developer remaining on the film. The developer is not readily neutralized by the stale fixing bath and the silver bromide is partially reduced to metallic silver to form the dichroic fog. An obvious remedy is to use a fresh fixing bath. Or, the film should be rinsed thoroughly before being placed in a used fixing bath. Then again, a short-stop bath can be employed to kill the action of the developer. Perhaps some photographers may object to the use of a fresh Left — Architectural Study. Leicaphoto by A. C. Elworthy on Agfa Superpan film. Center — Action photo. Photo by A. C. Elworthy. Perutz Fine-Grain Film; 1/200 sec. f:6.3. Right — Stage Scene. Photograph by E. Kyrmse, with a Leica Camera and DuPont Superior Film. Then moisten the backs of the prints with alcohol (70 per cent medicated alcohol, obtainable at any drug store), using a wad of cotton or similar material. Place the prints between blotters and put a weight on them, such as a stack of books, etc. Many dealers have ideal print presses for amateur use in the form of two boards between which the prints and blotters are placed and the whole tightly pressed together by means of a canvas belt. The procedure thus far described may be the one followed by many amateurs, but the reason for their failure is the fact that the prints are left under pressure for an insufficient time. In many cases it is merely over night, which accounts for the prints still curling at the edges. The prints should be left in the press for at least two or three days. When they are removed at the end of this time they will be perfectly flat. While on the topic of flattening prints we may mention a point in relation to chromium ferrotype tins. Sticking of the prints To these tins can be avoided by wiping the tins with a moist chamois before the prints are applied. Developer for Local Application: In some cases, to obtain the proper effect, a specific part of a print may reguire greater development than the print as a whole. In such a case the print is developed normally, rinsed in water to stop further development, and then the portion of the print reguiring further treatment has developer applied to it. It is necessary that the developer used for local application be relatively viscous so that it will not spread to other portions of the print. For this purpose glycerine or syrup can be added to the developer. It is then applied with a brush. When the particular portion has received sufficient development, the print is again rinsed and placed in the fixing bath. Catalogue of Schneider Lenses: A new and interesting catalogue on the Schneider lenses is being supplied by Burleigh Brooks, 127 West Forty-second Street, New York City. The reader may obtain a copy of this catalogue by writing to Mr. Brooks. Using an Old Fixing Bath: Whenever possible, it is always best to use a fresh fixing bath for miniature negatives. An old fixing bath may produce dichroic fog. A negative having this detriment appears yellowish green by reflected light and pink by fixing solution for every one to two rolls of film because of the expense. It must be remembered that after being used to fix one or two rolls of film, the hypo solution is still suitable for fixing prints. A separate container can be kept at hand into which the hypo is poured after it is used for films, to be used for fixing papers in the future. That Dust Problem: Suggestions for removing dust from the negatives during printing are constantly offered, and here is another one tendered by a miniature camera photographer. Draw the film through a folded chamois before it is placed in the enlarger. Diffusing Mediums: At times the photographer will desire to diffuse the light from his lamps to get softer effects. He must take into account the fact that the diffusing medium cuts down the illumination. If a meter is employed it will be a simple matter :o measure the diffused light to obtain the necessary exposure. When artificial light tables are referred to, a conseguent longer exposure will be necessary, according to the diffusing medium employed. Silk transmits from 62 to 75 per cent of the light. Ground or pebbled glass has similar effects. White opal glass transmits still less light — 50 per cent of the light directed at it. The photographer must allow a reguisite increase in exposure when diffusing his light. Large Trays: Some photographers may become ambitious this winter and desire to make large prints, such as 16x20 inches, or even larger. The miniature camera worker may feel that the cost of trays accommodating the large size papers is a little beyond his budget. It is a simple matter to make trays at home. They can be constructed from wood and then treated with a few coats of molten paraffin or a chemical resistant paint as Kodacoat or Probus paint, to render the trays leakproof as well as impervious to the action of the processing solutions. In this manner the cost of making relatively large prints is reduced. A Bit of Advice: Quite often in this department advice has been given to use slower films in preference to the super-speed emulsions, whenever it is possible to do so. The slower films will produce a finer grain, yielding sharper enlargements. Now we will mention a point in reference to speed lenses. Such objectives on high-grade miniature cameras are generally of superb construe Please mention The International Photographer when corresponding with advertisers.