The Centre for Fortean Zoology was founded in the UK in 1992 - nearly 20 years ago. Over the past two decades it has expanded to become a truly global organisation. We opened our American office in 2001, our Australian office in 2009, and now - in our 19th year - we are proud to welcome CFZ Canada to the CFZ global family.

Wednesday 7 August 2019

Thermal Imaging is Hot

We do love our toys, but are they really helping? In the case of thermal imaging, absolutely. While "night vision" and other heat dependent electronics may not work for ghost hunting, they are essential for cryptozoology.

Thermal imaging is the product of studies involving Thermography. Infrared thermography (IRT), thermal imaging, and thermal video are all examples of infrared imaging science. Infrared radiation is emitted by anything with a temperature above absolute zero. Absolute zero occurs at a temperature of 0 degrees Kelvin, or -273.15 degrees Celsius, or at -460 degrees Fahrenheit. At that temperature there is no heat and movement, so virtually every living thing should be detectable with this technology. Typically, cameras detect radiation in the electromagnetic spectrum and produce images of that radiation, called thermograms Thermography makes it possible to see one's environment with or without visible illumination. The amount of radiation emitted by an object increases with temperature, and each temperature shows up on thermograms as a different color. Humans and other warm-blooded animals become easily visible by day or night because they are warmer than their surroundings. With more specific equipment, physiological changes in human beings and other warm-blooded animals can also be monitored. Thermography is used for clinical diagnostics, allergy testing, veterinary medicine and mammography. It is also used to detect illness at airports and other ports of entry and in firefighting to see through smoke, find people and locate hot spots. Maintenance people use thermography to locate overheating joints and sections of power lines so they can be repaired before a catastrophic failure. Construction workers can see thermal signatures that indicate heat leak and improve insulation. 

The equipment required is a camera and a screen. It can be done with still photography or live scenarios. It's important for fieldwork to also include the ability to record and save the collected data. This is not always built in. The appearance and operation of a modern thermographic camera is often similar to a camcorder. CCD and CMOS sensors mostly work in the visible light wavelength range. By utilizing the infrared spectrum called near-infrared (NIR or "trailing"), and by using an off-the-shelf CCTV camera, it is possible under certain circumstances to obtain true thermal images of objects with temperatures at about 280 °C (536 °F) or higher with good clarity and contrast. Specialized thermal imaging cameras use focal plane arrays (FPAs). They respond to longer wavelengths like InSb, InGaAs, HgCdTe and QWIP FPA. The newest technologies use lower cost, uncooled microbolometers as FPA sensors but the resolution is much lower. Quality of resolution increases with the more expensive models but even the lowest cost ones are more expensive than traditional cameras. Higher-end models are often export-restricted due to the military uses for this technology. Some require cryogenic cooling to be functional. 

Thermograms are visual displays of the amount of infrared energy emitted, transmitted, and reflected by an object. There are multiple sources, and it is difficult to get an accurate temperature of an object using this method. The camera uses a thermal imaging camera is capable of performing algorithms to interpret that data and build an image. Even with good detail, the image only shows the viewer an approximation of the temperature. It uses multiple sources of data based values that compare the areas surrounding the object to determine that value rather than detecting the actual temperature. If the object is radiating at a higher temperature than its surroundings, power transfer will be taking place. Power will be radiating from warm to cold following the principle stated in the second law of thermodynamics. So if there is a cool area in the thermogram, that object will be absorbing the radiation emitted by the warm object. The Second Law of Thermodynamics, about the quality of energy, states that as energy is transferred or transformed, more and more of it is wasted. This Law also stated that there is a natural tendency of any isolated system to degenerate and become more disordered. The ability of objects to emit is called emissivity. To absorb radiation is called absorptivity. In the outdoors, cooling from wind may also need to be considered when trying to get an accurate temperature reading. The camera is only able to see electromagnetic radiation that is impossible to see with a human eye, so it builds a picture in the viewer. One slight drawback is that the camera will change the temperature of the object being viewed. 

Fortunately, while this is something to be considered in health diagnosis, it should not affect hunting for Fortean animals. We just don't need that level of sophistication. For an IR film to work thermographically, it must be over 250 °C (482 °F) or be reflecting infrared radiation from something that is at least that hot. Night vision infrared devices image just beyond the visual spectrum, and can see emitted or reflected near-infrared in complete darkness, but are not usually used for thermography due to the high temperature requirements. They are instead used with active near-IR sources. "Starlight-type" night vision devices generally only magnify ambient light. Both Starlight technology and digital night vision amplify whatever available light there is, while thermal-imaging (infrared) devices look at heat. Starlight technology is what most people think of when they talk about night vision. It does not work in complete darkness.Most of these devices also come with a built-in infrared (IR) illuminator that emits a beam of near-infrared light, invisible to our eyes, to illuminate the scene enough to be
detectable. This is how "trail cams" work, and while you can see good images, you can't see their heat. This is a reasonably priced option for most cryptozoology fieldwork, but sometimes the IR needs to be more specific. Consider the Sasquatch. Night vision equipment will detect the outline and presence of the animal, but only if it is fairly close; close enough to emit at least a little visible light. Moonlight usually provides enough light. In near complete darkness, as in a dense brush or moonless night, using only a night vision camera may not be effective. Thermal imaging, however, can measure the level of heat the animal emits. Further, it may also highlight the distribution of this heat which in turn makes it better for establishing size, species, and physiological elements. If Sasquatch is closely related to humans then the "hot spots" on his body will be comparable to the hot spots on normal humans. It will detect the position of various parts of the body, immediately discerning if it is upright and generally where the heart is. For those who propose that Sasquatch (or Mothman or hosts of others) are alien in nature, this is crucial debunking or supporting. Alien beings probably won't have their hot spots in the same locations and patterns that we do.

Night vision devices come in three accepted generations of design. Components and technology remain mostly constant and the levels measures can be thought of as sophistication levels. Different design generations significantly differ in image quality, cost and capability. Newer technology, often called "Generation 4". Generation II, III and IV devices use a microchannel plate for amplification. Generation IV is more adaptable to changing light conditions. It also is a better ion barrier which decreases the number of electrons that are rejected by the others, resulting in less image noise. The disadvantage is the overall decrease in tube life but this is largely negated by the low number that reach 15000 h of operation before replacement.

One of the major misconceptions about night vision devices is that they are like a binocular. Instead of focusing the light into the eye or similar lens, the light is converted to electrons that are then amplified and projected onto a screen that converts them back into a visible light image that you look at through the eyepiece or saved media. Photons from a dimly lit source enter the lens and strike the photocathode. The photocathode releases electrons, which are accelerated to the higher-voltage microchannel plate. Each causes multiple electrons to be released from the microchannel plate, which are drawn to the higher-voltage phosphor screen. Electrons that strike the phosphor screen cause the phosphor to produce photons of light view-able through the eyepiece lenses. The United States Air Force experimented with panoramic night-vision goggles (PNVGs) that double the user's field of view to around 95°. They are in service with A-10 Thunderbolt II, MC-130 Combat Talon and AC-130U Spooky aircrew, and are also popular with special forces. Ceramic Optical Ruggedized Engine (CORE), produces a higher-performance Gen 1 tubes by using a ceramic plate. Edge distortion is improved, photo sensitivity is increased, and the resolution is improved. This technology from about 2012 is starting to be used in contact lenses as well.

Some countries regulate possession and or use of night-vision
devices. Hungary and other European Union members strictly regulate the possession and use of these items. German law forbids such devices being mounted on firearms. Belgium has a similar law, but there even possession is considered illegal.In Iceland, the use of night-vision devices for hunting is prohibited, but are not otherwise restricted. New Zealand requires restricted access to the equipment and of exporting it, but not prohibited on the ownership or use of night-vision equipment for shooting non-indigenous game animals. In the US, thirteen states prohibit the use of night vision equipment for hunting, with 17 more have additional restrictions. In California, it is a misdemeanor to possess a device "designed for or adaptable to use on a firearm." Similarly, Minnesota law says as of 2014, "A person may not possess night vision or thermal imaging equipment while taking wild animals or while having in possession [an uncased and loaded weapon] that could be used to take wild animals." There is an exception for law-enforcement and military use of course. In those restricted states, you could probably argue lack of intent if you aren't carrying a weapon, but realistically we should be carrying a weapon of some kind into the woods.

The original purpose of night vision was to locate enemy targets. It is still used by the military for that purpose, as well as for navigation, surveillance and targeting. Police and security often use both thermal-imaging and image-enhancement technology, particularly for surveillance. Some researchers claim that the use of IR or night vision tends to deter Bigfoot activity. They claim that they aware of it. Primates are unique among in that they are able to see the red end of the light spectrum. Most all other mammals cannot see red, and no known mammal with night vision can see infrared light.

Some who work in the field assume trail cameras are omitting IR
light and that this is what wards off the beasts. In reality,they only emit IR when they take a picture or are video taping. The author of "The Bigfoot Field Journal" blog states he adapted a night vision rifle scope to fit to an HD Video recorder. Aside from the mental image of a guy in a ghillie suit with a role of duct tape, this is problematic in several ways. First, the scope is quite narrow so you are limited in your available range. Second, he uses the camera zoom function hoping to get a better enhancement. Most camera zooms don't really increase quality, they just make a bigger picture. This level of scope also has limited contrast. The author then enhances and stabilizes the image video, which further changes it. From a forensic standpoint, this renders anything captured completely unusable.

The Bigfoot Field Research Organization (BFRO) claims they are "the only scientific research organization exploring the bigfoot/sasquatch mystery." This is a bit of an insult to those in the field who actually are using science (and common sense) to research. They recommend using the CamTrakker system which is probably a standard night vision camera. No specs are available on their website or on the recommended link, and this cam is not available on Amazon. One reseller has it listed on ebay at $25.00 . The presumed quality of this equipment is a far cry from anything significantly scientific. Matt Moneymaker recommends a FLIR 1. FLIR is generally not a bad brand, but the FLIR 1 is an accessory used on a cell phone. He claims it is a thermal imager, but as it does not operate well below -4C which is a problem in many presumed Bigfoot habitats. It may be acceptable with regard to clarity and density capture, but it only has a thermal resolution of 160 × 120; and only an hour of battery life. Clearly not a research oriented camera. Also, it uses MXS technology, which is image fusion/combining for output that appears with more clarity. For scientific research purposes, it isn't clear if the output is truly clean, raw data, not an automatic change via enhancement or fusion. Thermal imagery cameras have come down considerably in price for consumers. As an add-on to your smart phone you can easily find something under $200. Brandon Hubbard, an architect, chose this year's best (2019) as the FLIR TG165. At about $350 it is also a good value, as it's cousin, the FLIR E60bx retails on Amazon for about $8700. Sometimes we have to compromise. Having a lesser quality camera at a do-able price is worth much more than one we don't have at all. Before purchase, please check to see if your local laws permit use, and that the sellers laws permit sale to your country.

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