International photographer (Jan-Dec 1934)

/„/v ig34 T h e 1 N T E R NATIONAL 1'HiiTOGRAPH E R Eleven for 5 seconds, and a successful print will be produced in New Paraphenylene-diamine — Glycin Formulas two minutes developing time. In a former installment of this department it was In order to avoid a hard line of demarcation between mentioned that paraphenylene-diamine tended to produce the two portions of the print, it is necessary to move the negatives that were lacking in contrast, especially in the cardboard slightly forward and backward with a rapid case 0f supersensitive films, and that it was desirable to movement. add glycin to the formula, to "pep" up the developer. Portions of a negative which are too thin because of The Edwal laboratories who market pure parapheny improper development, exposure, etc., can be shaded out lene-diamine under the trade name of DiamineP, and in this manner and a successful print produced. purified Glycin, supply the following formulas which they At times, especially in portraits, it will be desirable to have tested with various films. Formula 1, for superspeed introduce diffusion to soften the hard, sharp lines pro fUms ;s especially to be recommended for it produces a duced by the highly corrected anastigmats supplied with g00d degree of contrast with such films which under ordi miniature cameras. This is simply produced by introduc nary circumstances give soft results. ing between the lens and paper a piece of gauze stretched Tr/~mi\,TTTT a 1 r in te ji j j t-u -n j fUKMULA 1. v or super-speed hints. across a cardboard or wooden frame. 1 Ins will produce a slight degree of diffusion so desirable in portraits and pic Diamine-P 6 grams 90 grains torial photographs. The degree of diffusion in this case is Glycin 6 grams n) grains dependent on the distance of the gauze screen from the Sodium sulphite (anhydrous).... 37.5 grams 1 \ [oz. paper; the farther its distance from the paper, the greater Water, distilled 500 cc. 1 pint is the diffusion. FORMULA 2. For regular pan chromatic and Cloth can also be utilized as a printing screen to pro orthochromatic films. duce unusual effects. If a comparatively wide mesh ma Diamine-P 5 grams 75 grains terial such as silk bolting cloth is placed in contact with Glycin 5 grams 75 grains the negative during printing, the result is that of a print Sodium sulphite (anhydrous).... 37.5 grams 1*4 oz made on a fine-mesh canvas. In order that the cloth lie Water, distilled 500 cc. 1 pint flat over the paper it will be necessary to stretch it across To mix: Measure out the water, warm it to 125° a cardboard or wooden frame. When the framed bolting or 150° F. Add the sulphite first, then the Diamine-P cloth is placed over the paper so that it is in direct contact and Glycin. Stir until completely dissolved, filter while with it, only a slight degree of diffusion is produced. On still warm and let cool in a tightly stoppered bottle. reversing it so that the thickness of the cardboard or T^/^nn/rnT a t r^ ■ i r ■ , i • i . j • . i . . fUKMULA 5. t or special hne-arain panchromatic paper of which the frame is made intervenes between the fi printing paper and the cloth, the degree of diffusion is r,. . ^ y nn • * j /-. i-jT • i j j u i • Diamine-P 6 grams 90 grains augmented. Lrreater diffusion can be produced bv placing n ,. , . . , , , N ~~ e b 1t/P i ji ji .i .1 r . .... % r oodium sulphite (anhydrous ).... 51. j grams 1 Vi oz. bits of cardboard beneath the trame to raise it higher from . v , ~ te ~fr ■ Ammonium carbonate : Z grams 3U grains tne PaPer . , , _. , „ ,. Water, distilled _ 500 cc. 1 pint An interesting screen known as the Simplex Etching T() mix. Dissolve the Diamine-P and sulphite, but Screen can be obtained, which when placed in contact with not the ammonium carbonate as for formulas 1 and 2. ..... . v,^,,.»^-~-. .~^~ ~ .m,„M ^^^^ _-..,.w..„^^„„„-^^. Just before using the developer add the ammonium car bonate (which must be finely powered) and stir until dissolved. Developing time for the above formulas is: 60-degrees F. (16°C) 36 minutes 65-degrees F. (18°C) 30 minutes 70-degrees F. (21°C) 25 minutes The Stone Laboratory offers the following formula: Diamol (Paraphenylene-diamine) 90 gr. Glycin 60 gr. Sodium sulphite (anhydrous) 600 gr. Water 16 oz. ■ *^ik is " Developing Time Supersensitive panchromatic 30 min. at 65°F. Panatomic 15 min. at 65°F. Plenachrome and Persenso 24 min. at 65°F. Neiv metal masks: Burleigh Brooks is marketing flexible metal masks to be used instead of glass negative carriers. Four slots hold the film in position over the opening in the mask. Bakelite vs. metal tanks: It is a well known fact that bakelite is a poor conductor of heat whereas metal conducts heat very readily. This fact can be utilized in controlling temperature with the use of either bakelite or metal tanks. The miniature camera gets great results when trained When it is desired to place the tank in a tray through on animals. which cool water is running in order to keep the processing solutions at a constant temperature, a metal tank is called the paper during printing, produces a print which appears for. Bakelite tanks would be of little use in such a case like an etching. The effects are very interesting when used because of the poor conductivity of the material of which for portrait and pictorial photographs. they are made. These special enlarging methods will suggest to the On the other hand, we may first cool our solutions photographer other means of obtaining unique effects, as and then place them in the tank. In this case a bakelite well as procedures to follow to obtain the most from a tank offers the greater advantage. If the temperature of negative. (Turn to Page 27) Please mention The International Photographer when corresponding with advertisers.