4io 



OPTICS OF MOVING PICTURES 



[Cn. XI 



FIG. 227. MECHANISM OF POWER'S No. 6 CAMERAGRAPH, SHOWING THE 



THREE-WING, OUTSIDE SHUTTER. 

 (Cut loaned by the Nicholas Power Company). 



of the objective determines the size of the screen picture for a given 

 screen distance. 



577. Lining up the moving picture machine ; Adjustment of 

 the light. The machine being assembled on the board, the parts 

 lined up mechanically as well as possible ( 51 +), the final steps to 





