This section is from the book "Complete Self-Instructing Library Of Practical Photography", by J. B. Schriever. Also available from Amazon: Complete Self-Instructing Library Of Practical Photography.
352. Printing is a method of obtaining, on paper or other material, positive pictures from negatives, which maybe either plates or films. The necessary apparatus is a printing frame, in which the sensitive surface of the paper, etc., is pressed into close contact with the face of the negative, and held in that position during the process of printing. The ordinary printing frame consists of a wooden box-shaped frame, having a hinged lid to allow of the examination of the picture during the printing process. (See Illustration No. 48.) Where film negatives are to be printed from, or a smaller negative than the size frame you have at hand, a strong glass is placed in the printing frame, which serves as a support for the small film or glass negative.
Loading The Printing Frame. To load the printing frame, remove the hinged lid and place the negative in this frame, gelatin side up. Next, place the fingers of your left hand underneath the printing frame, so as to push one end (the end nearest you) of the negative up above the printing frame. Then, with a camel's hair brush or a piece of soft dry cloth, carefully dust the plate by drawing the cloth or brush over the negative and toward you. This will remove all the dust from the negative and out of the printing frame. If you dust the plate without raising it above the printing frame, it will simply remove the dust from parts of the plate, but not from the printing frame, and it might work back on the negative again. These little particles of dust, if allowed to remain on the negative or in the printing frame, will cause white specks on the print. Never attempt to remove the dust by blowing on the negative, as saliva is liable to be blown on the film, and the least bit of moisture would cause the paper to stick to the negative. (See Illustration No. 49.)
354. When ready to print, place the sensitized paper on the negative, the emulsion side coming in contact with the film. (See Illustration No. 50.) Then place the back of the printing frame in position, press down the springs and fasten tight. The printing frame is now loaded and ready for printing. Place the printing frame in strong daylight. (See Illustration No. 51.) If you have carefully cleaned the glass side of the negative, you can place it in direct sunlight. The effect of the light coming through the negative to the sensitive paper will be to gradually print the image from the negative onto the paper. The thin or transparent parts of the negative print first and change the paper from white to a dark color, thus producing the image.
Blue Print Paper. The simplest of all processes for making prints is undoubtedly that known as the Ferro-Prussiate, or Blue Print process, in which, as the name indicates, the pictures are a bright blue. There are many different brands of this paper on the market and they can be purchased at any photographic supply house. While the instructions which are sent out by the manufacturers are generally found to give good satisfaction, we deem it advisable to give the following short instruction.
Illustration No. 48Printing Frame.
See Paragraph No. 352
Illustration No. 49 Dusting Plate in Printing Frame See Paragraph No. 353
Illustration No. 50Loading Printing.
See Paragraph No. 354
Illustration No. 51Printing Frame in Position.
See Paragraph No. 354
Illustration No. 54Sliding Prints From Box Cover into Toning Bath.
See Paragraph No. 391