FOG EQUIPMENT.

Star (Christchurch), Volume LXVI, Issue 20295, 3 May 1934, Page 1

FOG EQUIPMENT.

Infra-Red Rays in Use at Sea. NEW YORK, April 28. A newly invented fog camera which uses infra-red rays to penetrate from two to four times further into thick weather than has ever before been possible has been installed on the steamships Manhattan and Washington, of the United States Lines. This camera was said to be the only effective means ever devised for overcoming this ancient enemy of shipping. By means of rapid mechanism, one picture is taken and developed every 30 seconds. By pressing a button illuminating the negative, the navigator mayhave a visual record of fog-hidden objects exactly one-half minute after the click of the shutter. Mr Flavel M. Williams, master mariner, who invented the camera, explained that its effectiveness depended for the most part on the type of fog encountered. “ Where haze alone exists in the atmosphere,” he said, ” the range of the camera is practically unlimited.” By way of illustration, he told of photographing the Atlantic highlands about six miles away on a day when haze prevented the unaided eye from seeing further than 800 ft. “ But where water vapour or solid particles, such as flue soot, are in suspension, together with haze, the range is cut down proportionately,” he added. Mr Williams, who has been naval officer, explorer and inventor of several electro-mechanical devices, has for some years been experimenting with the infra-red as applied to photography. A number of pictures of New York's sky line from great distances which have been widely reproduced throughout the country came from his experimental work. Essentially the same process is incorporated into the fog camera, he said, except that it was necessary to provide for a very rapid development of the negative to make it immediately available to the navigator. Every second lost after the shutter clicks carries the ship that much farther into the area which will be visible on the negative when it is developed. Therefore, he devised a system whereby, a continuous film passes behind the shutter, is quickly clipped after each exposure, and the section dipped at once into concentrated developer, and in a few seconds is put into the “ hypo ” solution where a light may be illuminated behind it, at the wish of the navigator. Mr Williams called the camera an experiment by the United States Lines, but expected it would prove to be an invaluable safeguard against what has been regarded as the most stubborn single obstacle to marine safety.