42 BIEDS 



used only on birds that are incubating or are perfectly 

 still and in good light. Many of the pictures used in 

 illustrating this book were made with the Adon, at moder- 

 ate magnification. (Fig. 3.) 



For speed pictures of birds flying or moving, a re- 

 volving back Graflex with its focal plane shutter and 

 rapid F. 4.5 Tessar lens meets all the requirements. It 

 cannot be dispensed with. Its hood and ground glass 

 permit you to see the object photographed up to the 

 instant of the exposure, and thus make it possible to get 

 good pictures of all moving or restless birds. Its rapid 

 F. 4.5 lens makes quick exposure possible on dark days. 

 The focal plans shutter works from time to 1/1000 of a 

 second. A 4x5 inch revolving back Graflex is a good size 

 to use and is the one usually employed. 



For tree or other climbing work where the camera 

 must be carried to great heights and anchored, a small 

 31/4x51/^ Tenax metal camera fitted with a Goerz Dagor 

 F. 6.8, six and one-half inch focus lens in a compound 

 shutter, is easily carried up to the vicinity of the nest 

 and is quickly anchored to a limb or the body of the tree 

 by fastening it snugly to the tripod. The focusing cloth 

 may be fixed over the camera and a few green leaves and 

 limbs quickly tied over it. 



I prefer plates to films for this work ; the Standard 

 Orthonon and Hammer Extra Fast ortho are both to be 

 endorsed as they give beautiful tone values. But there 

 are a number of other equally as efficient plates on the 

 market. 



