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.
Window Portraits. Very interesting At-home portraits may be made close to a window. In all such cases a portion of the window should be included in the picture space. Ordinary lace curtains supply sufficient diffusion of light to give roundness to the portrait. The subject should be placed far enough away from the window to illuminate the front of the face. Locate the camera almost on a line with the window, but a trifle further away from the wall than the subject. Any article of furniture may be employed; a large chair, settee, or sofa filled with pillows make good accessories. The walls of the room will serve as a background. The best results are obtained with window photographs when the sun is not shining on the window, as then there is more even illumination and the high-lights are not harsh. See Illustration No. 8, which shows good examples of window portraiture. The largest possible opening should be employed. Two or three seconds exposure will be sufficient. The plate should be developed in normal developer. The Universal Developer given in Volume II is especially recommended for this work.
Practice Work. For first work select a well lighted room, and one or two subjects. Have them assume natural, easy, careless positions in a portion of the room where the light conditions are best for the work. Place them so that the light will fall upon one side of the face. Place the camera so as to get either a broad or a shadow lighting, according to preference. If a window is admitted into the view, show only a portion of it, and then work against the light; or, in other words, on the shadow side of the subject. Work as far from your subjects as possible to admit as much of the room as is desirable. Be sure to place subjects so they will occupy one end of the picture, having the other end broken with some small piece of furniture, or other object, to balance the picture space.
139. Focus on the principal subjects, regardless of furniture and surroundings. Stop down only enough to give clear definition to the figures introduced in the picture. If clear definition can be had without diaphragming the lens, so much the better, as the larger the stop employed the shorter the exposure can be made.
140. Be careful to shield the lens from cross lights. Should there be lights reflecting upon the lens, shield it with the slide of the plate-holder, with your hat, or anything that will obstruct direct light falling on the lens. Of course, be careful that the shield is not placed between the lens and the view. The best protection to the lens is to prepare a cone to fit over the lens barrel, as is described further along in this volume.
141. When ready for the exposure, make two negatives of the same view, carefully developing them, one at a time. In the development of your second plate be guided entirely by the results of the first. Make proofs from both negatives, noting on the back of each all data connected with the production of the results, and preserve them in your proof-file for future reference.