Each coelacanth has a unique pattern of white markings, which enables scientists to identify individual fish.
Pictures of coelacanths (Latimeria chalumnae) swimming off the South African northeast coast are being streamed on the net.
The event is part of a scientific expedition that will help researchers determine the size and viability of the colony recently discovered in deep water in Sodwana Bay.
The coelacanth is sometimes referred to as "old four-legs" because of its distinctive and very large-lobed fins. It fascinates scientists because it is the modern representative of a group of fishes that swam in the seas before there were any back-boned animals on land.
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This is one of the reasons that the coelacanth has also been dubbed a "living fossil", and why the first sighting of a live specimen in 1938 was hailed as one of the major zoological discoveries of the 20th Century.
An expedition is now back among the fish to film them and study their habits. Video footage and still photographs of the coelacanths are also being displayed on a website for surfers to view moments after divers have delivered the images to the surface. The website is a subscription service charging a $10 entrance fee.
"We spotted an adult about 1.3 meters (over four feet) long and filmed it for five minutes,'' expedition head Pieter Venter said on Monday.
"It was fantastic as we were getting a bit nervous after four days of searching, three of them below 100 meters. The visibility and conditions were great and we'll go back Tuesday in the same area.''
Each coelacanth has a unique pattern of white markings, which enables scientists to identify individual fish.
The current expedition hopes to film more of the creatures so scientists can eventually determine if the Sodwana population is a viable and breeding one or is simply comprised of a few drifters from the Comoro Islands.
Divers can spend only 12 minutes at such depths and may take as long as two hours to go back up to the surface because they need to take decompression stops at different depths.
In November, one cameraman who filmed the fish died after surfacing without proper decompression - the second of three deaths that have been linked to the search for South Africa's coelacanths.