451. Exposure

Exposure. In making the first exposure, cut a sheet of the sensitized paper into narrow strips (about an inch wide). One of these should be placed on that part of the negative showing the highest point of light as well as the deepest shadow. (This is done, of course, when loading the printing frame.) As stated in a former paragraph, the distance to hold the printing frame from the light is the diagonal measurement of the negative, or, for a 4x5 plate from 6 to 7 inches. Weak or thin negatives require less time than dense or strong negatives.

452. Thin negatives, or negatives of average density (size 4x5 or smaller), printed on the regular or carbon grades, will require about 50 seconds' exposure to an oil lamp, about 30 seconds to a 16 C. P. electric or 4-foot gas burner, and about 10 seconds to a Welsbach burner. If, after developing, you find the print too light or too dark, try another strip of the sensitive paper, being governed in the second exposure by the result secured on the first strip. If the print flashes up instantly in the developer and turns dark in a second or two, you will understand that it is overexposed and half the exposure will be sufficient. If, on the other hand, the print develops slowly and gradually turns gray and foggy, more exposure must be given. If the print develops flat with proper exposure, dilute the developer with water - about one-fourth - and you will gain more contrast. If the print develops contrasty use full strength developer, as the weak developer gives contrast and the strong developer gives softness even to flatness.

453. Negatives vary greatly in density and lamps supply different strengths of light, so it is impossible to give definite directions for making the exposure. Until you

Illustration No 55 Printing at End of Table

Illustration No 55. Printing at End of Table

See Paragraph No. 449

Illustration No. 56 Developing at Table

Illustration No. 56 Developing at Table.

See Paragraph No. 449

Illustration No. 57 Applying Paste to Back of Print See Paragraph

No. 468

Developing Or Gaslight Papers Regular Grades 010072Illustration No. 58 Method of Picking Up Prints after Applying Paste

Illustration No. 58 Method of Picking Up Prints after Applying Paste.

See Paragraph No. 468

Illustration No. 59 Bringing Paste Side of

Illustration No. 59 Bringing Paste Side of.

Print into Contact with Mount

See Paragraph No. 468

Developing or "Gaslight" Papers - Regular Grades. 245 learn to judge the density of the negative you should always use the test strip. When the correct exposure is obtained in this way, a full size sheet of paper can then be printed and all subsequent prints should be equally good.

454. Compare the next negative you wish to print from with the first one, being guided by the exposure given that one. In a short time you will be able to estimate the exposure required for any negative.