HANDBOOK OF PHOTOGRAPHY 



A more modern box-camera shutter is shown in Fig. 2. It consists of two moving 

 parts and two springs. When the exposure trigger is depressed, shutter cover 14 

 moves from a position in contact with stud 15 (Fig. 2A) to stud 16. In so doing, 

 cam edge 25 of the shutter cover contacts stud 18 on the shutter blade, moving it 



Fig. 2. — Shutter of modern box camera. 



across the face of the camera so that the opening in the shutter blade, 26, comes 



opposite the opening 4, thereby exposing the film. When the trigger is released, 



spring 11 causes the cover to move from its position in B to its original position in A. 



Another, more complex, single-blade shutter is shown in Fig. 3. A is a view of the 



individual parts of the No. 1 Kodo shutter 

 of Eastman Kodak. B shows the assem- 

 bled shutter. 



Figure 4 shows how a disk diaphragm 

 operates to provide four different sized 

 openings for the lens to permit an adjust- 

 ment for varying light conditions. 



Before going on to shutters of more 

 complicated design, it will be advisable to 

 define more accurately the different parts 

 of an interlens shutter and describe their 



5.- --=^ ^1 



Fig. ZA. Fig. 3S. 



Fig. 3A. — Parts of No. 1. Kodo shutter for box camera. 1, speed pointer; 2, speed- 

 pointer rivet; 3, opening lever; 4, opening-lever rivet; 5, blade controller; 6, blade-opener 

 rivet; 7, trigger spring; 8, trigger assembly; 9, trigger screw. 



Fig. 35. — Modern box-camera shutter, completely assembled. 



function. In general, an interlens shutter has a casing which serves as a lens holder 

 and contains three separate units: 



1. A diaphragming device to provide an adjustable aperture for the lens. 



2. A blade mechanism to open and close for exposure. 



3. A retarding device to slow down the action of the blades from maximum speed 

 of action, thus providing a series of definite time intervals and a lever which can be set 

 to operate the shutter at any one of these intervals. 



