LAPSE-TIME PHOTOGRAPHY 33 



other things, an adjustable shutter from closed to 

 wide open; a hand crank making eight pictures a 

 turn; also a one-to-one shaft for lapse-time work. It 

 must have a detachable magazine or method of focus- 

 ing without exposing the roll. One cannot estimate 

 the position or focus of subjects a few inches from 

 the lens by scale. It should have lens extensions en- 

 abling a focus from infinity to an inch or less from 

 the subject. An outfit doing this cannot be had for 

 less than $500 at present. For lenses the camera 

 should have a wide angle, of one-half inch focus; the 

 regular one inch one and a telephoto of two to four 

 inch focus, all of the best make and fastest speed. The 

 telephoto will be used the least but is very necessary 

 when required. Also an extra magazine is very neces- 

 sary if doing color work, as one can be loaded with 

 Kodachrome film and the other with type A Koda- 

 chrome for pictures made with artificial light. 



My present lapse-time motor gear is an evolution 

 from the first one. When I started the work I had a 

 continuous running motor, geared down so that by 

 shifting belts I could get a change of speed from 

 thirty pictures a second in microscopic work to thirty 

 minutes between each picture. The lights were shin- 

 ing on the subjects continuously, burning consider- 

 able electricity, and tiring the plant. The continuous 

 running of the motor, from days to weeks at a time, 



