The Technion researchers findings were presented at the Institute of Electrical & Electronics Engineers (IEEE) Conference on Computer Vision and Pattern Recognition in Washington, DC in June.
"Underwater photos tend to be degraded and lacking in clear details because of the 'veiling' effect of ambient light," explained Schechner. "From above the water's surface, ambient light scatters into the line of sight - an effect commonly known as 'backscatter.' This causes poor visibility in even the clearest water."
Schechner and graduate student Nir Karpel realized that photographic images could be greatly improved by eliminating the backscatter effect. The two then developed an algorithm that - combined with a polarizing filter readily available for $20 to $100 - compensates for backscatter.
Schechner and Karpel worked on the method for a year and a half before achieving a breakthrough. The pair connected a special filter to a camera, which together with a mathematical algorithm they developed, led to excellent results. The photos the two photographed, at a depth of 26 meters in the Gulf of Eilat were of significantly better quality than anything previously done without the filter and the algorithm. It is possible to clearly see objects that previously appeared blurred and out of focus, or were not seen at all.
The new technology has great potential application in a variety of fields, including checking underwater pipes and cables, bridge pylons sunk in the water, sailing vessels and atomic reactors. It also could be of great assistance in scientific research (biology, underwater archeology and underwater mapping), as well as for amateur underwater photographers, who until now could only get good results using close ups.