Data: The instrument is a relative 

 gravity meter and must be calibrated at a 

 known station. It is used only in the slope 

 mode, i.e., the rate of change of the beam 

 position is recorded with time on a strip 

 chart. The generated slope is read as a 

 change to the spring tension of dial divisions. 

 The dial divisions are then converted man- 

 ually to mgal (0.001 cm/sec^). The range is up 

 to 12,000 mgal ±1-2 mgal. 



Photography 



A variety of cameras and techniques for 

 their employment has been devised for use 

 aboard specific vehicles (Fig. 11.14). Basically 

 there are two options: Mounting the camera 

 outside of the pressure hull, or photograph- 

 ing through the viewport. On BEN FRANK- 

 LlPf two 70-mm cameras and a television 

 camera were mounted externally on a pan 

 and tilt mechanism forward. The television 

 camera was monitored internally and served 

 to aim the 70-mm cameras. A strobe light 

 furnished the lighting. A second system en- 



Fig, 1114 Various still camera and strobe configurations: a) STAR III iwitti plankton 



sampler and cameras arranged lor stereoptiotograptis. b) STAR II and c) PC-3B with 



single camera and strobe, d) Pan/Tilt unit with two 70-mm cameras, a TV camera tor 



aiming and a light, (a S b USNUSL, c & d NAVOCEANO) 



554 



