Few who saw the movie The Silence of the Lambs could ever forget the final scenes where the serial killer stalks FBI agent Starling through a darkened house with night-vision goggles. If you’re like me, you kept hoping the agent would somehow perceive the killer’s presence. Remarkably, she did. She survived, and we all went home relieved.
The ability to see in the dark adds a whole other layer of awareness. That extra benefit on the water might also save your life.
During the past five years, more and more anglers have installed infrared (thermal) and low-light cameras aboard their vessels. These special “eyes” not only help anglers navigate at night, but also help them see water-temperature breaks, currents, birds and other marine animals that might signal fish.
“I can see hard temperature breaks of 3 to 5 degrees. It looks like the yellow-brick road,” says Capt. Bob DeCosta, who runs a 35-foot custom boat with a FLIR M-Series M626L thermal/lowlight camera out of Nantucket, Massachusetts (508-228-5074, albacorecharters.com). “You definitely see rips and tidal edges, and for us up here in the Northeast, we can see whales and birds that signal fish.”
Heat and Light
The use of night-vision cameras transitioned from military and commercial to recreational vessels as technology accelerated and prices began to drop — mostly within the past decade. FLIR Systems (flir.com) introduced Navigator, Voyager and M-Series mounted cameras followed by its handheld First Mate series in rapid succession.
“In 2006, we started installing thermal cameras in BMWs as a $2,000 option,” says Andy Teich, FLIR’s president. “We saw it as a useful feature for drivers. We used that automotive market to drive down the cost of thermal detectors and made them viable for other applications. Boating is kind of an ideal application for thermal imaging” — no streetlights and no forward-burning lights.
Thermal imaging differs from low-light viewing in several ways, though DeCosta says he uses both functions — flipping between the two views to see which provides the best picture in varying circumstances.
“Thermal works great in total darkness,” says Mike Bader, CEO of OceanView (nightboating.com), pointing out that the company’s top seller is the Apollo II, which combines thermal and low-light viewing. “But it seems the typical boater wants to cover all spectrums and use both technologies simultaneously at the helm.”
Thermal imaging requires no visible light to create a picture, while lowlight technology employs ambient light from the moon, stars, vessels or harbors. That ambient light bounces off remote objects and back to the camera to produce an image — the same way our normal vision works. But low-light cameras use very sensitive detectors and employ other ways to better gather the light that our eyes might not absorb.
By contrast, thermal night vision depends on the heat that every object emits and heat that reflects from objects. Thermal wavelengths can also penetrate smoke, light fog and haze, though they are inhibited by rain and soaking fog. In addition, thermal cameras can’t see through glass and isinglass; however they can see through glare on the water, because glare is reflected light not heat.
A thermal camera detects infrared radiation in the wavelength range between 7 and 13 micrometers. The camera’s detector material (vanadium oxide for FLIR products) absorbs the radiation and begins to heat. The resulting change in electrical resistance is the basic sensing technique, according to FLIR.
“Everything gives off heat,” Teich says. “You may find a semisubmerged log, and that will have a different temperature than the surrounding water, and the thermal camera will allow you to see it.”
Safe and Secure
Most mounted night-vision cameras range in price from $5,000 to more than $100,000. FLIR’s handheld First Mate MS thermal units — released this summer — start at $1,999. They differ from the original First Mate series because they’re scopes rather than cameras, allowing users to view but not record images.
Cameras come in a range of resolutions and lenses that generate narrow to wide fields of view — though thermal cameras can see greater distances than low-light cameras — and with different refresh rates. With a handheld or lower-range, fixed-mount camera, anglers might see a lobster pot at about a half-mile, a small boat at about a mile and a larger vessel at about five miles. With higher-performance systems, users might triple those distances, or even multiply them by 10 with top-of-the-line gear.
Camera companies produce a variety of pan and tilt options for the mounted camera heads, as well as several control setups. FLIR, which acquired Raymarine last year, has integrated its controls into Raymarine’s E-Wide and G series multifunction displays. OceanView has worked with Furuno to create onscreen controls through NavNet 3-D units.
DeCosta, who uses Raymarine C-series MFD units, operates his M-Series camera with a joystick. Besides using the camera in fishing situations, he simply finds it helpful when navigating to and from the tuna grounds. “I have a two- to eight-hour run depending on where the tuna are,” he says. “This year, I fished Georges Bank — a 140-mile run. I point the camera straight off the bow; it’s amazing — you can run right through a lot of lobster gear and high fliers (commercial-longlining gear) in the water.”
In port, he can navigate unlit harbors using the camera instead of just his radar. “The night-vision camera took all the guesswork out of it,” he says. “It’s just like running in daytime.”
What’s next in thermal-camera evolution? Teich says to look for dual-use systems that combine navigation with home-port security. Once you’re safely back in your slip, your thermal camera becomes part of an alarm system that draws an imaginary trip wire around your vessel.