3/8 KEPOKTS ON THE STATE OF SCIENXE. 



{h) The same persons who -were taken in side-face should be photo- 

 graphed also in strictly full-face. The focal plane should be that of the 

 front of tlie cheek. 



(c) The same persons should be photographed also, if possible, so as to 

 show the top of the head. This, however, is only of value if the subject 

 is bald or shaven, or has very close- cropped hair. 



It will add much to the value of the portraits if the same persons 

 have also been measured. 



C. Full-length Portuaits. 



At least twelve adults of each sex should also be photographed at full 

 length, standing, with heels together and arms by the sides. They should 

 be as nearly nude as circumstances permit, and each should be photo- 

 graphed in three positions : — 



(a) Full face, with the right arm hanging loosely by the side and the 

 left held across the body between the breasts and the navel, with the 

 fingers extended. 



{h) Profile with arms hanging loosely by the side. 



(c) Back view, with arms in the same position as in (6). 



Of these the full-face view is the most important, and the back view 

 the least important. 



For general directions as to pose, ttc, see below. 



General Directions. 



Camera and Lens. — Tn all cases record should be kept of the focal 

 distance of the lens and of the distance of the sitter from the camera. 



A lens of short focus should be avoided. The ordinai-y field camera 

 is usually fitted with a lens of about 8 inches focal length, but for cabinet 

 portraits nothing under 15 inches is satisfactory, and professional photo- 

 graphers often use lenses of considerably longer focus. Valuable results 

 may even be obtained with a telephotographic lens such as is employed in 

 geographical work. 



Rapidity of lens and plates is an advantage : uncivilised folk are im- 

 patient subjects. But note that very rapid plates are often too delicate 

 for field-work. 



The focussing screen must be kept vertical, and the swing-back 

 should on no account be used in focussing. Otherwise distortion of the 

 image is inevitable. 



Size and Scale. — The portraits should be on such a scale that the 

 distance between the top of the head and the bottom of the chin shall in 

 no case be less than 1|- inch (30 mm.). Smaller portraits are of com- 

 paratively little value. 



For composite work greater uniformity of scale is required. The best 

 results are obtained when the distances between eyes and lips are taken 

 as the constant dimensions. 



Tn every series it is more important that the portraits should be of 

 uniform scale among themselves than that they should be precisely of any 

 standard scale, but the following hints will aid in securing the latter 

 result also ; — 



