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.
Artificial Light. While it is perfectly practical to make prints by daylight, yet, for the first experiments, we advise the use of artificial light (kerosene lamp, gas or electric light). Daylight being so much stronger, the beginner is apt to meet with many failures, while artificial light allows of more latitude and less danger of over-printing.
Loading The Printing Frame. First, with a soft cloth remove all dust from the printing frame and cover; then with the same cloth clean the glass side of the negative. If a film negative is used, the back of the film must be carefully cleaned and the plain glass that is used in the printing frame, to support the film must be thoroughly cleaned on both sides. Next, lay the frame on the table, remove the back, and place the negative - gelatin side up - in the frame. Lift one end of the negative up above the printing frame; then, with a camel's hair brush (or a piece of soft cloth), carefully dust the plate by drawing the brush over the negative. If brushed without raising the negative out of the frame, the dust would only be carried from the plate into the edges of the frame, where it will cause white specks on the print. (See Illustration No. 49.) Next, on the shaded side of the table (See Paragraph 449), away from the direct light, place the printing paper on the negative, having the sensitive side of the paper come in contact with the film side of the negative.
445. The sensitive surface side of the paper must come in contact with the face of the negative. To detect the sensitive side, you will note that these papers are packed in small packages, face to face, while in gross boxes the paper is packed all facing one way. The paper, almost always, curls a little, the sensitive side curling in.
446. In the regular medium weight papers, one can judge the sensitive side by the sense of touch. Catching one corner of the paper between the thumb and the first finger, the side that feels smooth is the sensitive side. Of course the fingers must be perfectly dry or they will stain the print. Another test is to bite a corner of the sheet and the side adhering to the teeth is the emulsion side. A further test is to moisten the thumb and forefinger just a little, squeeze the corner of the paper, and the sticky side is sensitive. Testing the first sheet of the package will supply you with the key to the remaining sheets without previous testing. Remember that the paper is packed face to face, in small packages, and all one way in gross packages, and also that it curls slightly toward the sensitive side. The paper must be kept dry and away from any water or trays containing water.
447. Having placed the sensitive paper on the negative,
Developing or "Gaslight" Papers - Regular Grades. 241 next place the back of the printing frame in position, press it clown and fasten both springs. The negative is now ready for printing.
448. The accompanying half-tone will illustrate the printing by a kerosene lamp; however, the same procedure can be applied to any light.
449. In Illustration No. 55, a lady, in the act of printing, is seated at the end of a table, on which is placed the lamp. One-half of the table is shaded by a large piece of cardboard, which is placed in the center. The distance the printing frame is held from the light is equal to the diagonal measurement of the negative, which distance is necessary to secure an even illumination of the negative. After sufficient exposure has been given, she returns to the other end of the table (shaded end, see Illustration No. 56). Here, besides the box or package of paper, are the different trays, as labeled - developing, washing and hypo - all ready for use. The sheet of cardboard between the lamp and the trays excludes all direct light, but allows sufficient diffused light for the student to watch the development of the print. As this cardboard is to prevent the direct rays of light from striking the trays or paper, it should be fully 16x20 inches in size.
450. To hold the cardboard in position a number of books can be placed on the table, but it would be much better to have a wooden base to prevent tipping; or, in place of this cardboard make a light wooden frame, 16x20, and cover it with yellow postoffice paper. This will give more light, and the light coming through the yellow postoffice paper will do no harm to the sensitized paper or the prints while developing.