The irradiance pattern was measured for the propagation of a collimated beam of light underwater. A neodymium-doubled green laser was transmitted horizontally at a six foot depth in Lake Winnipesaukee, N.H. The irradiance was measured at distances from 0 to 100 feet and for off-axis angles from 0 to 58 degrees. The water had an attenuation length of 4.54 ft/ln and an absorption coefficient of 0.0446 ln/ft. The ratio of attenuation coefficient to absorption coefficient was 4.94. The fractional power contained within a cone of various angles was computed. At 20 attenuation lengths only 10% of the total power is contained within a cone of 4 degrees whereas at 4 attenuation lengths this same cone contains 50% of the power. (Author).

In The Underwater Eye, Margaret Cohen tells the fascinating story of how the development of modern diving equipment and movie camera technology has allowed documentary and narrative filmmakers to take human vision into the depths, creating new imagery of the seas and the underwater realm, and expanding the scope of popular imagination. Innovating on the most challenging film set on earth, filmmakers have tapped the emotional power of the underwater environment to forge new visions of horror, tragedy, adventure, beauty, and surrealism, entertaining the public and shaping its perception of ocean reality. Examining works by filmmakers ranging from J. E. Williamson, inventor of the first undersea film technology in 1914, to Wes Anderson, who filmed the underwater scenes of his 2004 The Life Aquatic with Steve Zissou entirely in a pool, The Underwater Eye traces how the radically alien qualities of underwater optics have shaped liquid fantasies for more than a century. Richly illustrated, the book explores documentaries by Jacques Cousteau, Louis Malle, and Hans Hass, art films by Man Ray and Jean Vigo, and popular movies and television shows such as 20,000 Leagues Under the Sea, Creature from the Black Lagoon, Sea Hunt, the Bond films, Jaws, The Abyss, and Titanic. In exploring the cultural impact of underwater filmmaking, the book also asks compelling questions about the role film plays in engaging the public with the remote ocean, a frontline of climate change.

Underwater Research is primarily a review of problems in underwater viewing and hearing and acoustics. The chapters in this book are papers collated from the symposia of the Underwater Association. This book explores the need for the further study of the physiological and psychological reactions of divers. The book also concludes that diving is still the best way in studying the benthic ecology and sunken wrecks and cities. The text is divided into 25 detailed chapters. Most of the topics in the text address the common problems encountered by divers such as in hearing and viewing. Specifically, problems in diver communication, depth estimation, color distinction are some of the topics covered. Other chapters deal with the psychological reactions such as anxiety, narcosis, and visual attention. Also, some chapters tackle solutions and experiments for the improvement of diving techniques and equipment. This reference is helpful to divers, students, and scientists involved in marine and environmental science.

Topics in this volume include: beam attenuation; optical properties of turbidity standards; optical absorptions of light and heavy water by laser optoacoustic spectroscopy; and refractive index fluctuations in seawater.