66 PHOTOGRAPHY FOR NATURALISTS. 



being selected of which clear definition could be 

 obtained at full aperture. It may here be mentioned 

 that one of the chief charms of fish-photography is that 

 of watching a sjioal of small silvery fish on the focussing 

 screen, especially. if they are lively, and such means as 

 are described below for illumination by reflected light 

 are adopted. The first exposure made was a shutter 

 one on one of the fastest plates obtainable. Develop- 

 ment with metol showed hopeless under-exposure, and 



Lampern. 



a few further trials confirmed the impossibility, under 

 such conditions, of an exposure which should be long 

 enough to secure a passable negative and yet short 

 enough to give a sharp image of fish in motion. 



An endeavour was then made to increase the light 

 available by the use of looking-glass reflectors, the 

 operator holding the shutter tube in one hand, while, 

 with the other, he manipulated the largest mirror he 

 could handle in such a way as to throw reflected sunlight 



