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.
Long, Prominent Noses. As a rule, this type of nose predominates with tall, slender people, and care must be exercised not to have the camera at an elevation above the nose. If the lens is above the level of the nose the full length of the bridge of the nose is reproduced, foreshortening the under side and exaggerating the nose in proportion to the balance of the face. If the camera is lowered sufficiently to foreshorten the bridge of the nose, showing more of the lobes, the nose will be made to appear less prominent and a more pleasing picture will be the result.
Short, Stubby Noses. Short, stubby noses should be treated in the reverse manner; raise the camera to look down on the bridge of the nose, which will give the effect of lengthening this feature.
239. There are no fixed rules governing this point, other than above mentioned, but these suggestions should be found very helpful. Be guided principally by your subject and the surroundings.
Short Neck. If your subject is a stout person, possessing a short neck, adjust the camera to a lower position, to show as much of the neck as possible. It is well, in such cases, to have the subject lean forward with shoulders thrown back slightly, thus extending the chest. More of the neck is shown when the head is held erect, and the appearance of stoutness is very materially reduced.
Long Neck. For securing the most pleasing likeness of a slender person whose neck is long, the treatment is just the reverse of that applied to those having short necks. The camera should be raised a trifle higher than the level of the mouth, the height being regulated, to a certain extent, by the length of the subject's nose. The figure of the subject should be turned from the light, thus elevating the shoulders and giving the neck a shorter appearance.
The Mouth. As the control of facial expression is governed principally by the mouth, one must pay strict attention to this feature of every subject. If it is closed too tightly, never request the subject to open the mouth. On the other hand, if it is open do not ask them to close it. In either case they are apt to go to the extreme. Converse with them, making it a point to ask a question on some subject certain to bring a pleasing answer; or even a pleasant remark requiring no reply will generally cause the mouth to shape itself naturally, and at that instant make the exposure.
243. When conversing with the subject does not bring about the desired expression, suggest the passing of the tongue over the lips, to wet them. This will produce a slight gloss on the lips, which helps to give a more natural shape to the mouth. In cases of chapped lips, the wetting of the lips with the tongue overcomes the appearance of the soreness and the chapping will not be visibly prominent.