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.
Using the open light, softly diffused in the space occupied by the subject, there are no dense shadows to contend with. Therefore the exposure will be approximately one-half that usually required for Plain Portrait Lighting. In case the lighting appears a trifle flat, use a stop one size smaller. This will slightly accentuate the small shadows and overcome flatness.
332. Development - As there are no strong highlights or dense shadows, it is best to carry the developing a trifle further than for ordinary portrait work. If the background is white the development must be carried still further, to obtain beautiful half-tones in the portrait. Exercise care lest the negative be under-developed, because it is no easy matter to judge the amount of density, owing to the fact that the whole plate is of an even tone. Use the Universal Developer, to which should have been added a few drops of a 10% solution of Potassium Bromide, or a little old developer, to hold the negative crisp throughout development.
Practice Work. Throw open the entire skylight and place the subject in proper position to receive good illumination on the face, showing a two-thirds view of it, and make the exposure. Then move the subject a trifle to the opposite side of the center, turning the face in the opposite direction, to secure a view similar to the other side of the face. Then, with the subject in the same spot, turn the figure from the light and the face toward the light, at a slight angle to avoid being broadside to the light. Now, move the camera to obtain almost a front view of the face, and, after making this exposure, place the subject a trifle away from the center and make a profile view. In each case place the opaque screen between the light and the shadow side of the face. (Two more examples of Schriever Lighting are shown in Illustrations Nos. 31 and 32.)
334. For the benefit of experience expose each plate slightly different, varying the exposures one second. Usually from one to two seconds time are sufficient for this. style of lighting. For experiment, expose the first plate
1 second, the second 2 seconds, the third 3 seconds, and the fourth 4 seconds, developing the initial exposure first. This will supply a key to the development of the others. By this means you can demonstrate in a most effective way the special advantages of this form of lighting.
335. Be sure that the skylight is wide open, and that enough light comes from the top to fully illuminate the top of the subject's head. Remember, it is necessary to employ opaque curtains to cut off a portion of the light, no matter what view of the face is being made. This opaque screen aids materially in producing roundness. Proof prints should be made from the resulting negatives, and filed in the proof file. Place full data on the back of each proof, giving complete information regarding the manner in which you proceeded to secure the results.