The Wilder Side of Thermal Imaging

0
960

SCREEN AFRICA EXCLUSIVE:

Written by Jeandré Gerding, WildEarthhead of Camera Operations

The WildEarth crew are veterans when it comes to bringing unbelievable live wildlife experiences to audiences around the world. Their popular interactive show, safariLIVE, has kept viewers glued to their seats for years, with virtual safari-goers tuning in daily to follow the lives of their favourite leopard, lion or elephant characters.

Just in case the technical and editorial challenges of broadcasting a live, interactive, unscripted, wildlife show from the middle of the African bush weren’t befuddling enough, another challenge is often thrown into the mix… darkness.  The team recently had to broadcast a weekly safariLIVE prime time special to Nat Geo Wild in the USA. This meant live filming on location in Kenya and South Africa would be in the wee hours of the morning, before the sun had risen on the continent of Africa.

While using normal white light might seem like a straightforward solution, the team was uncomfortable with the ethical challenges it would present. Shining visible light onto the scene of a hunt would alter the outcome: a hapless gazelle could be temporarily blinded by the light and not see an approaching lioness. Illuminating the lioness may allow the gazelle to spot her stalking, allowing the cat’s dinner to run off and see the light of another day. In general, artificial light profoundly changes the conditions in which animals live. Nocturnal animals have a whole suite of physical adaptations, behaviours and survival strategies to cope with darkness – as have diurnal animals. Shining bright lights on any animal completely alters their natural conditions.

Unobtrusively observing nature’s spectacles is at the core of the safariLIVE ethos. Infrared lights, which are invisible to both humans and wildlife, have been used by the team for a number of years in an effort to have zero impact on animals. However, for the team’s camera operators on location in South Africa’s Sabi Sands (within the greater Kruger National Park), infrared technology is far from an ideal solution. Despite having sensitive cameras capable of picking up low lux levels, the bushy terrain means that the invisible infrared light reflects off trees and shrubs. This makes it near impossible, in many situations, for the infrared camera rigs to capture the action unfolding behind the foliage.

Fortunately, FLIR has provided the safariLIVE team with technology that was once only reserved for elite military operations. Unlike traditional cameras, which depend on reflected light to produce an image, FLIR’s thermal cameras detect the heat energy radiated by animals (or any other objects), and this translates visually into animals becoming their own light sources.

Thermal technology has been around for a long time. In 1947, the first thermal line scanner was developed for use on bombers and cargo ships at the start of the Cold War. The camera was bulky and took an hour to produce a single frame.

Even today, most thermal cameras are limited to nine frames per second (9Hz), with extremely low resolutions such as 320×240 or even 160×120 pixels, making them unattractive options for the broadcast industry. Further complicating things, thermal cameras can’t use traditional glass for producing lenses because it reflects thermal radiation. Instead, exotic materials such as germanium, zinc selenide or sapphire are used to produce thermal optics. This means that most thermal cameras have a fixed prime lens that is not ideal for filming live wildlife.

This is where FLIR’s technology really stands out. SafariLIVE is now able to capture high-definition thermal imagery with the company’s masterpiece – the FLIR T1K (T1020) camera. This camera is capable of producing 30 frames per second (30Hz), has a choice of three interchangeable lenses and packs the most pixel resolution into any thermal handheld camera on the market, producing stunning images of resolutions up to 2048×1536.

With the help of WildEarth’s engineering department, a dual camera night rig was created with the FLIR T1K top-mounted on a low-lux infrared camera. This allowed the team’s talented cameramen the option of either camera, depending on the sighting. In many situations they operated both simultaneously, allowing the show’s director to cut between the two feeds.

David Eastaugh, a senior camera operator at safariLIVE, can’t throw enough superlatives at the T1K: “I’ve really enjoyed using this camera, as it not only has tremendous practical uses but is also great at producing images with cinematic quality. Thanks to its large sensor [uncooled microbolometer] and array of advanced FLIR OSX Precision HDIR lenses, we are able to achieve a shallow depth of field and make our subjects really pop with the camera’s fine temperature control. This allows us to see what’s beyond the bush and stick with the action, without interfering.”

The team’s senior director, Kirsten Mclennan-Smith, shares a similar view: “As a director, I love cutting to the FLIR when an animal is on the hunt and the action is heating up. The FLIR ensures we have great content on the screen. This way, you’re not interrupting [animal behavior] and it’s more engaging for viewers.”

The team at safariLIVE is immensely excited about the future possibilities of thermal technology, as it allows viewers to connect and fall in love with nature in a new way, which might help to create future conservationists. Importantly, this technological advance also allows anti-poaching units to protect the animals that the crew and viewers love more effectively.

For readers living in South Africa, you can catch a new season of safariLIVE every Sunday night on SABC3 from 18h30 to 19h30. Those outside of South Africa can catch the action on natgeo.com/safarilive.

LEAVE A REPLY

Please enter your comment!
Please enter your name here