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.
162. With the light correctly diffused and falling on the subject at the proper angle, and with the posing complete, you are practically ready to make the exposure. At this point, however, you should notice each feature of the light and pose, making sure that nothing of importance has been overlooked. The following outline covers the cardinal points which must be considered when making a bust picture according to the rules of Plain Portrait Lighting:
163. Place the subject in the strongest light.
164. The angle of light is controlled by the shades directly above the subject.
165. One shade directly over the subject should be drawn sufficiently to supply the angle of light.
166. The light farthest from the subject supplies the general illumination, and should be wide open.
167. The opening of the skylight should be V-shaped.
168. The light should fall on the subject at an angle of 45°.
170. Too much side-light causes shadows to fall straight across the face.
171. The drapery must fall in natural folds, not be wrinkled.
172. Alterations or changes desired in the pose must be made as easily as possible, without calling the subject's attention to the defects.
173. Give particular attention to the position of the head with reference to the various features, so they may not be exaggerated.
174. Improve the features by posing the head properly.
175. The background should be at least three feet to the rear of the subject.
176. The subject should be well centered with reference to the background, so the edge of the ground will not appear within the picture space.
178. The expression of subjects is governed to a great extent by the manner in which they are handled.
179. Hard, chalky high-lights should be softened by using the diffusing curtains on the skylight.
180. The general control of the light on the subject is secured with the diffusing screen.
181. The use of the diffusing curtains gives general illumination and lightens the shadows.
182. There must be a gradual blending from the highest lights to the most dense shadows.
183. If, after having manipulated the diffusing curtains, there is a harsh line between high-lights and shadows, use the reflector.
184. The reflector should be placed at an angle of approximately 45° with the skylight.
185. The strongest reflected light should be thrown on the front of the face.
186. Under no circumstance should reflected light be thrown strongly onto the ear and back of the shadow cheek.
187. The effect of lighting should be to produce roundness, with even gradation throughout.
189. The head should be turned toward the light until the tip of the shadow cast by the nose just blends with the shadow of the cheek.
190. The catch-light in the eye should be in the upper corner of the iris, nearest the source of light.
191. The catch-light in the eye should not extend into the pupil, nor into the white of the eye.
192. The catch-light and the shadow cast by the nose are the keys to correct lighting.
193. To give proper shape to the shoulders, the hands should be placed midway between the knees and the hips.