5 Video Camera 



Two types of underwater video camera deployments were tested. The Coastal 

 Engineering Research Center ROV is maneuverable and contains an underwater 

 video camera. In addition, a higher resolution, low-light camera was brought on- 

 site for testing. The original intent was to mount the low-light camera on the 

 magnetometer sled to allow filming and real-time visual monitoring of the bottom 

 as the magnetometer surveys were being conducted. Although the low-light 

 camera was specified as non-metallic, onsite testing revealed that there were 

 enough metal parts in the camera to contaminate the highly sensitive 

 magnetometer signal. This prohibited its use on the magnetometer mount. Thus, 

 the low-light camera was deployed as an independent sensor via mounting on the 

 ROV and on a towable v-fin. 



Ideally, remotely operated underwater cameras are controlled from a 

 motionless vessel. However, the project safety plan prohibited anchoring of 

 manned vessels, and strong tidal currents and wave action at this site caused 

 significant vessel drift. Thus, both the ROV and the low-light camera were towed 

 over the bottom in the same areas but independent of the other instruments. 

 Areas viewed during the video tows are shown in Figure 4. 



Video image observations revealed the bottom borrow areas to be sandy with 

 some rhythmic topography (sand ripples) and occasional coarser sand/gravel 

 streaks (usually in the troughs between the sand waves/ripples). Several pieces of 

 suspected ordnance were observed. The video tows included several drifts to the 

 north of borrow area 1 A. Here, the camera passed over a bottom which changed 

 from clean sand to hummocky-clay zones. The clay was scarred with current 

 marks. Bottom debris (plastic, ceramics, metal, and suspected ordnance) were 

 observed in these clay zones. 



Chapter 5 Video Camera 21 



