Page 293 - The ROV Manual - A User Guide for Remotely Operated Vehicles 2nd edition
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282 CHAPTER 10 Video
matter increases scattering. Both absorption and scattering present difficulties when optical obser- vations are made over appreciable distances in water.
Scattering is the more troublesome, as it not only removes useful light from the beam, but also adds background illumination (Figure 10.37). Compensation for the loss of light by absorption can be made by the use of stronger lights, but in some circumstances, additional lights can be degrading to a system because of the increase in backscatter. These circumstances are analogous to driving in
FIGURE 10.37
Illustration of the scatter phenomenon.
FIGURE 10.38
(Graphic by Deepsea Power and Light.)
Separation of the light source from the water column before the camera mitigates backscatter.
(Graphic by Deepsea Power and Light.)
