Night Vision / ThermalCapability ComparisonThe term "night vision” actually covers two technologies:Image Intensification and Thermal. Thesetwo technologies have undergone significant development over the past 25 yearsand made tremendous leaps in the past 15 throughout the Global War on Terror. They have provided unprecedented advantagesto the warfighter on the battlefield and law enforcement professionals in theirnever ending struggles to keep this country safe. And like most technologies born on thebattlefield, tactical eventually becomes practical. With the rising popularity of nighttime hogand predator hunting in the United States, more and more hunters are findingthemselves shopping for night vision gear. Night Vision Hunting has become the fastest growing segment of thehunting market and many hunters are asking: "what type of device is best forme?” The law enforcement community isasking itself these same questions as many agencies are finding a need tobetter equip themselves at night in order to keep the streets safe.
With the sudden surge in night vision popularity amongprofessional end users and sportsmen, it is important to understand thedifferences in the technologies offered on the market. Often times, the capability requirements ofboth end user groups overlap. To thisend, we wanted to put forth an education primer on the general performancecapabilities of image intensifiers and thermal devices. Please note that there are many differentbrands, makes, models, etc. available. We are well aware (and you should be too) that the performance range canvary greatly depending on the device. This article is not going to get into a brand vs. brand or model vs.model battle. The intent is to providegeneral information that can be extrapolated over most night vision devices onthe capabilities of the various technologies. This discussion is aimed at providing end users with an idea of whichtype of device will be most beneficial for their mission.
Let’s begin by discussing the differences between the twotypes of night vision.
Image Intensifiers are more commonly referred to simply as"night vision.” For the remainder of thearticle, I will refer to image intensifiers as "night vision.” Night Vision uses a powered image intensifiertube to produce a light-amplified image to the user. The tube literally amplifies existing ambientlight to produce a bright, detail-rich image. Traditional night vision produces a green image to the viewer. Green is the most visible color to the humaneye. We can see more shades of greenthan any other color in the visible light spectrum. As such, the green phosphor screen in theimage tube presents the most hues and shades to the user, allowing him/her tobest resolve the image in detail and depth. This is an important positive capability in that night vision users cansee into the dark and gain positive identification of their surroundings andtargets. Since night vision is simplyallowing you to see in the dark, it is completely possible to achieve positiveidentification of faces, clothing, animals, etc. This is perhaps the most important aspect ofnight vision. Since night vision devicesare mostly used in conjunction with a firearm, the ability to achieve 100%Positive Identification (PID) is critical before taking a shot. Night vision will allow the user to readsigns as well. Another important aspectof night vision is that it allows for easier depth perception while moving. Because the tube is amplifying existingambient light, shadows and terrain undulation can be more easilyidentified. This helps night visionusers to gauge distance using terrestrial association. The key benefit to night vision is itsidentification capability.
However, despite the benefits of night vision, it is not aperfect tool. Like our eyes, we aresusceptible to being fooled by camouflage. Nature has the ability to camouflage people, animals, and objects simplyby placing foliage in front of them. Sometimes, possible targets will go out of their way to camouflagethemselves in the terrain. Bad guys canwear camouflage clothing and attach foliage to their person. Animals often have natural camouflage intheir coats. The same camouflage thatworks for a person or animal during the day will work just as well, if notbetter, through night vision (after all, the image is the same as normal, butnow being presented in a single color palette). Night vision may also be slightly harder to use during inclement weatherconditions such as rain, snow, fog, and smoke. Another, more obvious, deficiency in night vision is that it only worksat night. However, we have to rememberthat night vision requires some amount of ambient light to function. Today’s Gen3 tubes can do much more with muchless light, we still need to have some illumination to gather. If you take a brand new Gen3 device into anabsolute pitch black environment, you will not have any image. At that point, an external infraredilluminator is required.
Thermal imagers work differently than night vision. Rather than amplifying the existing light inan image, thermal uses a special detector that senses infrared energy. Infrared energy is produced by everything inthe world, whether natural or man-made, and increases as its heat rises or it producesfriction. So essentially, thermalimagers detect heat, providing a starkly contrasted image where heat-producingtargets and objects will light up against their cooler surroundings. This trait makes thermal imagers ideal fordetecting targets in the user’s environment. The most obvious use for thermal devices is easy detection of targets inthe field. The warmer an object is, thebrighter it will appear in the thermal device. An animal or person that is hiding among foliage will more easily bespotted against the landscape since the user is not depending on the shadingand tones of the target for detection. Detection is the most important aspect of thermal imagers. These devices will allow users to quicklydetect the presence of a possible target against a wide range oflandscapes. Thermal imagers can also beuseful in tracking blood trails and, depending on the time lapse; foot prints. This can be useful in finding suspects oranimals. Thermal is also capable ofseeing through light rain, snow, fog, and smoke. Another positive trait for thermal devices isthat they can be used during the day. Night vision will eventually become damaged when exposed to too muchlight for extended periods of time. Thermal devices can operate regardless of the ambient light present. This includes high noon or absolute pitchblack. Though, thermal devices do tendto work better at night because the ambient environment will have cooled down,increasing target contrast.
While thermal devices excel at detection, they are not asuseful for identification. It ispossible to get a decent level of identification capability out of a thermal ifit is a high resolution system (such as 640x480). However, facial recognition and PID is notgenerally possible. Thermal is alsoincapable of reading text printed on a flat surface. This is most easily demonstrated by lookingat a sign or a garment. If the lettersare raised or have a different finish than the rest of the surface, it may bepossible to make out the graphic, but you will not get nearly the legibility ofnight vision. Positive Identification isperhaps the biggest drawback to using thermal. Obviously, the higher resolution systems will be able to resolve moredetail in an image. However even theyare going to be lacking in the ability to clearly identify someone’s face orone type of animal from the next. From aprofessional standpoint, this means that identifying an armed suspect from anarmed officer is going to be more difficult. For hunters, it can make it more difficult to tell the differencebetween a coyote and dog. Though, we cansurmise differences in our thermal targets by observing their movement andbehavior, it is important to remember that we are most often dealing withfirearms in conjunction with these devices. Once the trigger is squeezed, the possible outcome is the loss of alife. The consequences of mistaking acalf for a hog can be a $13,000 bill from the ranch owner. The consequences of mistaking a good guy fora bad guy can mean life in prison. Andthe consequences of mistaking someone’s dog for a coyote can mean the dog’sowner hunting you down. The issue isexacerbated at distance since electronic zoom cuts the image resolution everytime. Thermal imagers are also incapableof seeing through glass. Because ofthis, their lenses are made from an expensive material called germanium. But this limitation can be detrimental tosurveillance operations, or if a hunter wants to observe the field from his/hervehicle cab. One last thing to considerwith thermal imagers is the video frame rate. Thermal imagers are active systems that provide the user a video on anOLED screen to view through the eyepiece. So unlike night vision, a user does not look "through” thermal and seethe world. Real time video runs at 60 Hzand some thermal devices display at this frame rate. But, most thermal units run at 30 Hz. This means that the video image you observecan experience some slight clipping during fast movements.
Again, the above information is a simplistic overview orthe characteristics and pros/cons of night vision and thermal imagers. Depending on the device you possess, some ofthe characteristics can vary. Now thatwe have established a baseline idea of the capabilities present in thesedevices, let’s take a look at how they are applied to some practical scenarios.
**DISCLAIMER**
We chose to bias these videos towards the first-respondermarket.
We felt they would best displaythe capabilities of the various night vision devices in different environments andcould be easily juxtaposed across the hunting and military markets aswell.
No live firearms were used in theproduction of these videos.
Also pleasenote that filming through night vision devices is incredibly hard to do becausethe focus of the night vision device and the camera are not always in perfectsync.
We did our best to provide asaccurate a representation as possible.
SCENARIO 1
This video is shot through a law enforcement officer’spoint of view. It represents theaftermath of a foot chase where the fleeing suspect would have thrown awayevidence in hopes of not being caught with it on his person. The suspect is in custody and we must nowsearch the area where the object was tossed in an effort to recover it forevidence.
In the first part of the video, we show the officer using atime-honored tool found on every peace officer’s duty belt: theflashlight. Most of the time, individualpatrol officers are not going to have access to night vision equipment, so theyhave to make do. During the flashlightsweep, we can see a ton of detail. Asthe officer walks along the brush line, he sweeps the light over the foliage. But at this distance, the light splash isalmost too bright against the leaves, causing a whiteout. This hinders the officer’s ability to seedetail and the outer spill of the light beam must be used. In fact, the light almost shows too muchdetail, effectively camouflaging the object in question. If wewere to extrapolate this scenario into a full-on search, it could easily besurmised that the officer(s) would be out there all night, searching a longstretch of brush to find whatever was discarded by the suspect.
The next part of the video shows the same scenario through anight vision monocular. In this case,the night vision helps the officer see a larger area lit up. But, the dense foliage still provides achallenge to the officer trying to find the discarded evidence. As mentioned earlier, the same camouflagethat works during the day is going to be just as effective at night. Another issue we see is the focallength. Night vision devices focus on afixed focal plane and must be manually adjusted to refocus up close. Users want to generally achieve a baselinefocus where objects will be nice and crisp from about 10 yards out toinfinity. But, night vision will notautomatically refocus when trying to observe things up close and must be donemanually. This can be challenging duringa search like this where the focal plane constantly changes. A long sweep of the area yields little resultand can be especially difficult it the officer is unsure of exactly what he islooking for.
The final section of the video shows the search while usinga thermal device. The first thing youwill notice is that the detail seems to be way less than the night vision andflashlight segments. This is becausethermal will generally have a harder time differentiating between cooler objects. You can also see that the undulation interrain as the officer walks up to the brush line, is more difficult toascertain and can make land navigation more difficult when using a thermaldevice. But in terms of accomplishingthe mission (finding the discarded evidence), the thermal device seems to winthe night. As the officer walks up tothe brush line, the heat signature of the discarded item is almost immediatelyvisible through the dense foliage. Theheat from the suspect’s body was transferred to the object and it is still warmenough to be visible to the thermal device after 15 minutes. The discarded evidence turns out to be apistol. On a side note: thermal, likenight vision, must be manually focused for up close detail duringobservation. While the point of thisparticular exercise was to find the evidence, you will notice that there is adistinct lack of detail up close when the gun was recovered because the thermaldevice was not refocused during the pick-up.
In the first scenario, thermal is the clear choice due toits awesome detection capability when compared to the other viewing methods.
SCENARIO 2
This video shows the point of view of a SWAT marksmanresponding to a hostage situation at a local business park. The armed suspect is using a hostage as ahuman shield in the front atrium as he communicates with the on-scene hostagenegotiator. The officer is given ordersto hold on the target, but must be ready to take a crisis shot on the suspectif negotiations break down and the hostage is thought to be in immanent danger.
We first see the officer’s view through a standard dayscope. As we can see, the darkenedatrium presents an almost impossible view. Movement can be seen through the building’s glass door, but withoutlighting, it is impossible to decipher what we are looking at. The officer cannot determine who the hostageis from the suspect. Everything is incomplete shadow making a crisis shot impossible and putting the hostage indanger. It’s not until the suspect makesthe hostage open the door that the outside lights provide enough illuminationto take a clear shot. However, if thesuspect closes the door again, the officer will be back in the proverbialdark. Clearly, the use of a standardrifle scope in this situation would not only put the hostage’s life in jeopardy,but it perfectly illustrates the handicap created when a responding lawenforcement agency lacks night vision capability.
In the second part of the video, we see the same situationplayed out through a dedicated 4X night vision weapon scope. Here, we can easily see into the darkenedbuilding and make out both the suspect and his hostage. We can see that the suspect has asemi-automatic pistol held to the hostage’s head and is standing behind him. In fact, the night vision image allows forclear identification of the suspect and his hostage. The officer not only knows where to shoot, ifrequired, but he knows who the suspect is. We can easily determine that the suspect is an adult male with shorthair and a larger build. We can see thatthe hostage is also an adult male with short hair, a beard, and an athleticbuild. We can even see when the suspectand hostage are speaking (or in the case of this role-play, we can see whenthey are laughing because the "suspect” is yelling out crazy stuff). When the door is opened, the outside lightscreate a slight bloom on the two individuals, but the level of detail and identificationcapability does not change. In asituation like this, night vision is giving the officer a commanding edge.
In the final segment of this video, we observe the samesituation through a thermal weapon scope. While the building is clearly seen to include the columns, lights, painton the parking lot, we are faced with a show-stopping problem: thermal does notsee through glass. While the hostagenegotiator is talking with the suspect, the marksman has absolutely no way ofobserving the situation, rendering him unable to take a critical shot shouldthe need arise. It is not until the suspectforces the hostage to open the glass door that we can even see that anyone isthere. When the pair are finallyexposed, the officer is given enough data to see who is who and that there is apistol to the hostage’s head. But, thethermal unit does not provide any facial detail. In this circumstance, the thermal scope isset to no magnification in an effort to retain as much resolution aspossible. Resolution is critical in thissituation because the officer may have to take a shot within a fraction of aninch. If he were to use the electroniczoom, he would lose resolution and hinder his ability to identify the criticalshot.
The night vision weapon scope is the clear winner in thisscenario. The standard day scope rendersthe marksman impotent to affect any type of resolution to the situation and thethermal scope was arguably a liability. Yes, the suspect and hostage became more clearly visible when the doorwas opened. But, without a green lightto take the shot, the pair could just as easily go back inside the atrium,placing the officer in the same situation again.
SCENARIO 3
The third scenario simulates recorded surveillance video ofa known drug deal/bad-guy meet location behind a local strip mall. The officers have set up in a concealedlocation to film this corner where criminal activity is often committed by gangmembers according local residents. Thehope is that the police department can identify the drug dealers/trouble-makersand start building cases against them. However, PID must be achieved in order for evidence to be admissible incourt.
The video starts out through a thermal imager. We can clearly see four subjects gathered inconversation at the back corner of this L-shaped strip mall. The overall height and build of the subjectscan be identified as well as their clothing type. It can be confirmed that we are observingfour grown males. All are wearing shortsleeve shirts while two are in shorts and flip-flops and two are in pants andshoes. Ball caps can be seen on all ofthem. We can clearly see the subjectsloitering about, talking and interacting with small electronic devices. The detail level is quite good overall. We can see that the shortest subject has abeard that gets longer at the chin and the suspect facing the camera also hasfacial hair. However, it is impossibleto identify the faces of the subjects or their ethnicity. We can certainly see other details such asthe fact that the subject facing the camera is wearing cargo pants and seems tobe chewing gum. When one of the subjectsmotions to something in the distance, causing the closest subject to turnaround, we can clearly see that he is wearing glasses and has a beard.
The second half of the video shows the same group ofsubjects through night vision. Again, wecan immediately recognize four grown males as well as their height andbuild. We can see that they are alllight-skinned; possibly White or Hispanic. While the ethnicity cannot be clearly ascertained, it is possible torule out that we are observing Black males or darker-skinned individuals. Clothing can be identified as two subjectswearing pants, two wearing shorts, and all wearing ball caps. Printed shirt graphics can also be seen aswell as the overall brightness/tones of the shirts. This information could be useful if a crimeis committed during the surveillance and the observing officers need to providean immediate description of the suspects to other officers. One of the main things to note is that facialfeatures can be recognized enough to identify individuals.
Both thermal and night vision provided a good nighttimesurveillance tool. The location wasquite dark with any surrounding light sources facing away from the scene. Regular video surveillance would have beenimpossible. Depending on the mission, thermal or night vision could make aneffective tool for monitoring individuals or areas. For a business or personal security system,thermal will definitely provide good data and allow users to recognizeprominent features on individuals. Nightvision provided this same data, but allowed the individuals to be identified. For professional use, this is an importantpoint. Law enforcement officers need tomake a case and be able to prove everything in court beyond a reasonabledoubt. Warfighters need to identifysubjects while working up target packages. But, civilian property owners may just need to see that there are peoplewho shouldn’t be there, doing things they shouldn’t be doing. In that case, either technology will sufficein the dark. This particular scenarioshowed a video from a good vantage point where the four subjects could beclearly seen. Obviously, this is notalways going to be the case during a surveillance operation. The thermal device being used was a 19mm640x480 1X monocular. The night visiondevice was a Gen3 monocular.
SCENARIO 4
In this scenario, we are put into the shoes of a lawenforcement officer providing perimeter security at the back of a commercialbusiness that is a front for selling drugs, during a raid. An undercover officer is inside. As the assault element makes entry at thefront of the building, we see two individuals go running out the back. The inner perimeter officer has a few secondsto determine what to do. Are they bothsuspects? Is one a suspect and the othera cop? As the two subjects run, we jumpto the point of view of one of the outer perimeter officers who witnesses thesame two subjects run through a gate into a residential yard. These situations can develop rapidly andradio communications can sometimes become garbled or confused. Usually, officers have very little time toprocess the situation and make a decision when use of force is called for.
At the start of the video, we are looking through a thermalimager and we see the first subject burst through the door, turn, and run awayfrom the camera. We can ascertain adecent amount of information. We can seethat he is male, athletic build, wearing shorts, T-shirt, and flip-flops. He appears to have some facial hair and isarmed with a pistol. The subject appearsto be trying to get away without regard to who or what may be in his immediateenvironment. The second subject followsclose behind the first. We can see thathe is male, larger build, does not have facial hair, and is wearing a shortsleeve shirt and pants. This subject isalso armed with a pistol. We can alsosee that his behavior is different than the first subject. While the first guy immediately came runningout the door and took off away from the camera, the second guy has his gun at alow ready and takes a quick glance forward before running in the same directionas the first. What does this tellus? The inner perimeter officer has acouple seconds to decide whether or not to engage the first, second, or bothsubjects. Neither subject’s face can beclearly identified through thermal, nor can their clothing. The first subject is probably a fleeingsuspect based on his behavior. But, isthe second guy a fleeing suspect or a fellow officer giving chase? After all, the raid is being carried out byofficers not in traditional uniform… The second guy seems to exhibit some moreprofessional gun handling behavior. Butat the same time, there are many bad guys out there with firearms and tacticaltraining today. Either way, the innerperimeter officer does not have enough data to engage these subjects withforce.
From here, we switch to the view of one of the outerperimeter officers. The two subjects randown the alley, away from the first officer’s position, went through a gate,and entered a residential yard. Theouter perimeter officer and his K9 observe the first subject running throughthe gate with the second right behind him. The first guy turns and both subjects draw down on each other. What do we do? At this point, it can be safely assumed thatone of the subjects is a cop and the other is a bad guy. But the situation is more complex than we seeon the surface. At first, we would thinkthat the guy being chased is the bad guy. But, as an outer perimeter officer, we know that there was an undercoverofficer inside the building. At theonset of the raid, he was going to run so as to not blow his cover. But, was his cover compromised anyway and heis being chased by one of the suspects who knows he is going to get caught, butis intent on killing this "traitor” before he goes down? Everything is happening in a split second andthe outer perimeter officer is about to watch two individuals, one of them cop,engage each other at close range. Hisheart is beating through his chest and the blood is rushing in his ears. The damn frogs in the pond behind him won’tshut up either. With the stress levelthrough the roof, he doesn’t have 100% PID on either subject to make a shot.
In the second half of the video, we see the same scenarioplay out through night vision. The innerperimeter officer can immediately see the same details visible in the thermalvideo: grown male subject with facial hair in T-shirt, shorts, flip-flops, andarmed with a pistol comes bursting out the back and takes off down the alley. The second subject is following close on hisheels. He wears a short sleeve shirt,pants, has no facial hair, and is also armed with a pistol. The differences start when we see that bothsubject’s facial details are visible and identifiable. The inner perimeter officer can get a quickglimpse of the faces and get an idea of who is who. But, as the second subject rounds the cornerafter the first, "POLICE” is clearly printed on the back of his shirt.
As the chase continues into the residential yard, the outerperimeter officer can clearly the see the same details as the two subjects drawdown on each other. Now, this splitsecond decision is able to be made because it is clear who the suspect is. The outer perimeter officer can engage thesuspect and help to save his buddy’s life.
While it is pretty obvious that officers equipped withnight vision devices would be better off in this scenario, there are otherfactors we should acknowledge. Thesevideos show great clarity and contrast of thermal devices. The subjects seem to literally pop out oftheir environments. It is incrediblyeasy for someone equipped with thermal to follow these subjects. The night vision devices allowed the officerto identify the subjects, but the detection limitations start to show. Notice how the first subject started to blendinto the tree line as he ran away from the inner perimeter officer. While night vision provided more depth to theimage, the light sources behind the tree line started to make it more difficultto follow the subjects. This can againbe seen in the residential yard. Whenthe first subject spins to engage the second, he is standing with a house andfoliage behind him. This helps toconceal him slightly. While he can beseen, he is not popping out of the camera as he does when viewed through thethermal imager. This is a complexscenario that shows benefits and deficiencies of both technologies. Night vision edges out thermal in this case,due to its identification capability, but it is not without its shortcomings.
SCENARIO 5
Here, we see another surveillance video that simulates adrug/contraband buy. We show twodifferent takes on this scene. The firstone has the suspect enter the truck on the driver’s side. Another subject approaches the driver’s sideshortly after and some sort of transaction appears to take place. The second take on this scene shows a subjectentering the truck on the passenger side. A transaction appears to take place, the subject exits the vehicle, andleaves.
As we saw earlier, thermal imagers do not see throughglass. So, vehicle surveillance becomesalmost impossible to conduct. The videostarts out with the suspected dealer entering the truck. It is impossible to determine if he is alonein the vehicle. Once he enters the cab,he is completely obscured from view. Wewatch as the second subject approaches the vehicle. We can see that he is wearing a T-shirt,shorts, flip-flops and hat. His beardcan be identified as well. Beyond that,there is no other facial recognition. Atransaction of some sort appears to take place where the outside subject handssomething to the guy inside the truck and takes something in return beforeleaving. As observers, we are completelyblind as to what is happening inside the truck through the thermal device. In fact, we cannot even be sure that thefirst subject who initially entered the truck is the same one interacting withthe second suspect who later approaches because we do not know if anyone elseis in the vehicle.
Next, we see the same scene play out through nightvision. As the suspected dealerapproaches the truck, we are able to get clear facial recognition. However, one of the deficiencies in nightvision becomes immediately apparent when he unlocks the truck and enters: halobloom. The headlights and mirror lightsare activated when the truck is unlocked and the scene is almost completelybloomed out for a few seconds. A lot ofthe bloom is actually exacerbated by the camera that is recording through thenight vision goggle. If we were to be lookingthrough the night vision device with a naked eye, we would still see somebloom, but not as bad as what a camera adds. Nonetheless, this issue with night vision must be taken intoconsideration when filming through night vision for evidence. Once the suspect is in the truck, the lightsare turned off and we can clearly see into the cab. We know that he is alone in the vehicle andwe can still clearly identify him. Wewatch as he talks on his cell phone. Later,we see the other subject approach the truck. His face is also identifiable, though there is some extra light from offcamera, which is somewhat washing out his face. We are able to see the transaction take place as the driver reaches forsomething under the dash or in the center console. The object is handed to the outside subjectand the exchange is complete. At thispoint, we have evidence that the original subject that entered the vehicle wasthe only one in the truck and carried out the exchange with the suspectedbuyer.
In the next take, we watch a subject approach the truckfrom the passenger side, through a thermal device. Again, we can make out his clothing andbuild, but we cannot get detail from his face. He enters the passenger side of the cab and completely disappears fromview. The subject stays in the truck fora little while and then exits and walks away. He is not visible again until he is out of the truck. At this point, we have no idea whattranspired in the truck, let alone have anything we can build a case on.
Next, we see the same scene play out through night vision. We watch the subject approach the truck whichalready is being occupied by a male driver, clearly seen through thewindshield. As the subject enters thepassenger side of the truck, we are again blinded in the video by the excesscamera bloom created by white light sources. Again, this is not typical when viewing auto-gated Gen3 tubes with thenaked eye, but is a factor you must contend with when filming. In the vehicle, we can clearly seeinteraction between the two subjects. Anexchange appears to have been made and the first subject exits the vehicle withsomething in his hand and walks away.
This set of videos makes it quite apparent that thermalimagers are not ideal for vehicle surveillance. While filming through night vision has its drawbacks in bloom created bythe camera from light sources, it is still the clear choice when one needs tosee through glass.
Night vision and thermal imagers are incredible tools thatoffer undeniable advantages to professionals and amateurs alike when operatingin the darkness. However, there is nomagic device that will offer a perfect solution for every situation. Like everything else, you must choose theright tool for the right job. Thescenarios above were designed to provide overall examples of situations thattoday’s professional could find himself in. The scenarios were meant to illustrate the capabilities and deficienciesfound in these technologies to aid you determining which one is best for yourmission. While these videos focused moreon the professional end-user, it is easy to look at the data and juxtapose itover the civilian’s mission as well.
This is the first in a series of comparison videos betweennight vision and thermal that we will produce at TNVC. The next series will focus more on ruralapplications. We hope you found thisdata educational, relevant, and enjoyable. Stay tuned over the next few months for more.
**UPDATE** 06/07/2016
SCENARIO 6
This video
is designed to simulate a search for an unarmed suspect that is fleeing
police. It could also be a lost elderly
person or dementia patient – doesn’t matter.
We’re trying to show you the benefits and limitations of different technologies
– not tell you a story. Anyway, we’ve
got a man in the woods, at night, under substantial tree canopy that is
obscuring ambient light from moon and stars.
And we’ve got to find him. For
the sake of demonstration, our subject remained in the exact same place during
filming.
The first
part of the video is a search using a standard flashlight. This tool is familiar to us all. Rural searches with flashlights present a
unique challenge. Foliage and other
natural terrain features can easily cause confusion because of the various
shapes. If the search is taking place in
a wooded area, the closer foliage will tend to catch a lot of the light from
illumination tools, limiting beam penetration.
This can create a claustrophobic effect because the observer’s vision
will be heavily limited. This is
illustrated in the video. The close up
branches appear extremely well-lit – almost glowing, while foliage as close as
15-20 feet is quite dim.
While bright
flashlights have a long reach in open spaces, they are often hampered by
close-up objects. The spider web of
branches in a densely wooded environment can soak up a lot of lumens – even
going so far as throw light back on the person holding the flashlight. As the viewer scans the area in the video, we
are quickly faced with the limitations of white light in a rural search. In the end, we are unable to locate the
subject in the woods.
Next, we see
the same search through image intensification night vision. Night vision goggles are great identification,
but limited in their detection capability.
The dense foliage in this video shows a worst case scenario for night
vision use. Effective camouflage will
work just as well at night as it does during the day. Natural vegetation provides excellent concealment
properties for humans and animals when viewed through night vision
goggles. It is important to note that
night vision is difficult to photograph and film through. The actual images we observed with the naked
eye looked much better than the video image seen here. However, the foliage created considerable
challenges in locating the subject.
While the
video was shot under relatively ample amount of moon/starlight, the amount of
light blocked by the dense tree canopy further hampered our ability to find our
subject. The sky looks relatively bright
through the trees and almost creates a backlight situation that makes the
foreground foliage appear darker. This
phenomenon is peculiar to wooded areas viewed through night vision
goggles. As the viewer pans to observe a
slightly more open area, the image brightens and more detail is seen.
Compared to
the white light search, we are able to better understand our environment and
see further into the environment. But,
we are still unable to locate the subject.
Lastly, we
observe the seen through a thermal imager.
The initial scan yields immediate results and the subject, partially
obscured by foliage, is seen right away.
The benefits of thermal in detection are undeniable and show how thermal
imagers are the best tool for this application.
Now, you may be saying: "wait a minute, the guy isn’t even hiding.” True.
He is halfway concealed by foliage with a large portion of his body
readily visible. But, go back and watch
the white light and night vision segments.
Even with that much exposed, he is still undetectable with the other
technologies. If the subject were to be
hiding further, the dense foliage would provide more camouflage than we see
here, but we would still detect him much faster as we moved through the
environment.
It is worth
noting that although thermal clearly allowed us to detect the subject
immediately, the technology is not without its limitations. The cooler foliage and lack of light/dark
differentiation provides less information for the viewer to navigate. Without light and shadow, the viewer would
have a much harder moving through the environment because it is more difficult
to determine near/far relationships in wooded areas. If the observer is hoping to maintain some
degree of stealth, they would not want to move through the environment under
thermal imaging alone.
SCENARIO 7
OK, OK so we
have a storyline for this one. This
video set puts us in the shoes of a police officer searching for an armed
suspect who fled into the woods. This
sort of pursuit is extremely dangerous because the situation favors the suspect
who may have no problem ambushing the officer.
The first
segment brings us back to white light.
In this case, the white light would be attached to the officer’s weapon
since he/she is actively searching for suspect who is known to be armed. As you can imagine, this sort of search is
practically suicidal, yet brave, under-equipped law enforcement officers face
this type of threat every night across the nation. While white lights provide users the ability
to see in the dark, they also give up your position/presence to anyone within
miles. Flashlight glow can be seen from
extremely long distances at night.
In this
scenario, the armed suspect has fled into the woods and the police are in
pursuit. They do not know if the suspect
is going to continue running or stop and ambush them. In the last wooded video segment, we observed
and discussed the effects of dense foliage on white light searches. That significant handicap is almost crippling
when you add in the threat of an armed opponent possibly laying wait to ambush
you. While the officer is sweeping the
area, "painting” it with the light and slowly moving through the brush, the
suspect has all the time in the world to set up position. They know exactly where the pursuing officers
are. At the conclusion of the white
light segment, the officer locates the suspect who has the drop on them. Their weapon is already aimed at the officer
and we see the result of this dangerous situation. Another brave law enforcement officer would
be lost in the line of duty.
The next
segment shows the same situation through the eyes of a pursuing officer
equipped with a generation 3 TNV/PVS-14 night vision goggle. Like the previous video in this series, we
see the effects of dense foliage viewed NVG’s.
The foliage makes detection challenging.
But, we can see much more detail and depth than what was visible through
the white light. Though perhaps the
biggest advantage is the officer’s ability to control his environment. As the officer moves, he can see everything,
while the suspect, unaided by night vision, is much more limited. Of course, the suspect may hear the
officer(s) moving through the woods in pursuit, he is extremely limited in
sight and has lost any advantage in knowing where they are. This uncertainty can severely hamper the
suspect’s will to fight. This is one of
the intangible benefits of night vision.
People are naturally uneasy in the dark because our primary information-gathering
sense is taken away.
As the night
vision-equipped officer moves through the woods, he intermittently uses his
infrared illuminator in darker areas.
Eventually, he locates the suspect, who may know the officer(s) is
close, but whose vision is so hampered by the darkness, he cannot know where
they are. The officer is able to call
out the suspect who, not knowing where the officer is or how many are out
there, realizes that they are in an unwinnable situation and surrenders. Even had the suspect decided to shoot it out
with the police, his not knowing exactly where they are while the officers have
him dead to rights, would create a decidedly one-sided fight. It is no doubt that night vision has
significantly increased officer safety in this situation.
The last
segment of the video sees us revisiting the scenario through thermal. Like night vision, thermal provides the user
the ability to completely control the environment. The suspect is literally in the woods, in the
dark. They may hear the pursuing
officers as they move through the woods, but they cannot see them unless they
get closer. The officer’s thermal
imaging device allows them to move through the terrain at their own pace. But, due to thermal’s superior detection
capability, the hiding suspect is almost immediately spotted. Night vision allowed the officer to detect
the suspect as well, but thermal was much faster. The suspect is called out and taken into
custody. The psychological effect on the
suspect is immense. If you are the bad
guy, hiding in a dark position, you are likely to have high levels of
confidence in your ability to dictate the terms of the fight. But, if you are unable to see your adversary
and are suddenly called out or otherwise engaged, the immediate shock/panic is
overwhelming.
While thermal
technology is again, clearly superior in fast detection, we must further
discuss its application in these scenarios.
We are observing the scene through the eyes of the officer behind the
thermal imager. However, there is no way
for the officer to engage the suspect through thermal – nor is positive
identification capable. Clearly, we are
able to see that the suspect is wearing a jacket and ball cap, but his facial features
are unrecognizable. While it is
improbable that there are other people hiding in the same area as the search,
the thermal user needs to be aware of the limitations. Obviously, the suspect’s behavior will
greatly aid in PID as well. But that
still does not address the inability to engage the suspect, should they become
violent, through thermal.
The only way
to successfully engage through thermal imagers is if the thermal happens to be
a scope with a reticle zeroed to a host weapon system. While this makes engagements extremely easy,
the limitations of PID through a thermal image should not be taken
lightly. For a warfighter deployed
downrange, it is pretty easy to justify smoking someone through a thermal
scope. Enemy combatants are easily
recognized as being armed through the thermal image. Their behavior of moving aggressively, lying
in wait to ambush advancing friendly forces, or planting IED’s is enough to
warrant sending them to Allah. You do
not need to be able to report with 100% certainty, their identity (at least,
this was the case when our Commander in Chief was in it to win it). Domestic law enforcement is held to a
different standard. Every nuance of an
encounter, violent or not, is looked at with a critical eye by our crazy
liberal society. While cops need to be
held accountable for their actions, especially when it involves loss of life,
they are too often made out to be "guilty until proven innocent” these
days. Currently, there is no case law
written about engaging suspects through a thermal scope. And while it may be incredibly easy to prove
that the deceased suspect was armed and engaging police when talking to a
common sense-thinking person, we have to look at every situation through the
eyes of a crazy liberal defense attorney who will bring the most asinine
loophole in the law to bear in order to bring into question the officer’s
judgment. At TNVC, we side with the good
guys and want to make sure police do not inadvertently place themselves in the
hot seat. That said, we want to make
sure that the officer in the video is backed up by NVG-wearing fellow officers
with IR-laser equipped weapons. The lead
officer detects and calls-out the suspect using thermal. The support officers identify the suspect and
are able to engage him with their weapons, should he decide to fight.
SCENARIO 8
This video
focuses on vehicles. The devices used
are the IR Defense IR Hunter Mk2 Thermal Weapon Scope and the D790 Gen3 Night
Vision Weapon Scope. While there is not
necessarily a storyline, we can juxtapose the footage with a law enforcement or
civilian application. The law
enforcement use is obvious: surveillance.
In the first part of the video, we see a dark colored minivan pull into
a garage, shown through a thermal imager.
We can easily see that it is a minivan.
The very sensitive 12um thermal core allows us to pick out the Chrysler
emblem on the hatch and the body styling lines quickly identify it as a Town
& Country. Now we have a make and
model. This information is obviously
important in collecting evidence to build a case.
After the
minivan parks, the camera pans over to the pickup truck parked next to the
garage. As seen with the van, the 12um core
of the IR Hunter Mk2 is sensitive enough to identify the outline of the badge
on the tailgate. We can see that the
truck is a Ford and the styling/size identify it as an F150. If we were building a case to prosecute a
criminal, we need to be able to prove that we were indeed looking at the
suspects’ vehicles. Chances are, we
would know what they drive, so being able to ID a Ford F150 and Chrysler Town
& Country would help the case (hey, soccer moms can be criminals too…). But, let’s look deeper.
The Achilles
heel of thermal imagers is their inability to see through glass. The activity in this scene is taking place
with the minivan. As it pulls in, there
is no way for us to see inside the vehicle.
We cannot identify the driver or how many occupants are in the van. And from this vantage, we cannot see the
driver exit the vehicle. If we were
trying to link this van and a suspect to a crime that just occurred, we would
not have the ability to do so based on this footage alone. For all we know, the driver is not the
suspect.
Another
important observation is that we cannot read the license plates on either vehicles. It simply does not show up in this
footage. Print is not visible to thermal
imagers unless it is a different temperature/reflective material from the
surface. There is a slight possibility
to read raised print (such as a license plate), but the angle would have to be
perfect. In this case, we cannot read
the plates, so 100% positive identification is impossible. Sure, we can say that we know the suspect
vehicles are a Ford F150 and a Chrysler Town & Country. But, it needs to be proven in court. Many families own both of those vehicles and
the inability of thermal to read those plates, unequivocally identifying these
vehicles as those of the suspect(s), we cannot prove the case. In court, the devil is in the details. This detail could be exploited by a criminal
defense attorney.
Lastly, let’s
observe an interesting phenomenon: color shade ID. The minivan appears to be dark. We cannot tell the actual color in a black
and white thermal image. But, we can
identify the shade of the paint, right?
The minivan appears dark; maybe gray, dark blue, red, or green. But is it?
Thermal can be tripped up by reflective surfaces. Rather than seeing the actual shade of paint,
the clear coat reflects the vehicle’s surroundings. In this case, the reflections are actually
creating an illusion. This fact is extremely
important to remember. What if a dark
blue minivan is witnessed fleeing the scene of a crime? Responding officers are trying to find the
suspect vehicle and only have thermal for use as night vision? This minivan fits the description of the
suspect vehicle "on the surface.” In the
chaos of trying to apprehend a dangerous suspect, the amped up officers might
think they have the vehicle pegged. But,
upon rushing in, they come face to face with a young family returning from
dinner… and a possible civil suit against the city…
The night
vision footage clearly shows the minivan as being very light-colored. While everything is green through the NV image,
there is no doubt that this vehicle is not the dark blue minivan reported
above. Another observation is that we
can clearly read the license plates using night vision. These details are extremely important in
acquiring positive identification of vehicles.
It is also interesting to note that we can see the parked truck is
actually a darker shade. The thermal
image made it look very light – possibly even white. That’s because the clear coat was reflecting
light. The night vision image, while not
showing color, clearly shows the vehicle is darker.
Another
interesting observation is how the tinted rear windows of the minivan
completely defeat night vision’s ability to see inside. Normally, night vision allows us to see right
through glass. But, window tint, even
the legal variety, will greatly hamper our ability to identify. In this case, we only get a view of the
vehicle’s rear. So, night vision does
not allow us to identify the driver either.
But, it does give us an edge in identifying other important
characteristics of the vehicles.
SCENARIO 9
In this
video, we are observing an armed individual walking in field of tall grass. Again, we are using the IR Defense IR Hunter
Thermal Weapon Scope and the D790 Magnus Night Vision Scope. This scenario was inspired by our customers,
many of whom deal with trespassers and poachers on their land. The first half of the segment shows a loan
individual walking a field against a tree line.
The subject is obviously armed with a rifle and wearing a helmet with a
night vision goggle. The thermal image
instantly detects the subject whether they are moving or standing still. Even when they crouch down behind a berm, the
subject’s head is incredibly easy to spot against the rest of the scene. While their face is not at all identifiable,
we can clearly see they are wearing long pants, a hooded jacket, and a backpack. As the subject stands up from their position
behind the berm, we are able to easily identify the weapon as an AR15 with a
suppressor.
After
changing the scope’s polarity to black hot, we can still clearly see the
subject – maybe even more so. Black hot
tends to increase the contrast of images and can make detection in open areas
even faster. The rest of the thermal
footage continues to illustrate how easy it is to detect subjects through
thermal. As mentioned, this scenario was
inspired by many of our customers who own large amounts of land. These customers are often looking for night
vision devices that will help them detect interlopers so they can avoid a
possible violent confrontation with poachers/smugglers, alert authorities,
etc. Simply using a flashlight lets
everyone in the area know you are there.
The use of night vision and thermal equipment allows you to maintain stealth,
increasing safety.
Next, we see
the same scene, but through night vision.
While the subject is still seen amongst the grass and tree line, they
are not as quickly detectable as they were through the thermal imager. The video is focused on the subject, but we
can imagine it would take some more effort to detect them if we were simply
scanning the field. The subject’s face
is a little more visible through night vision.
However, the main point of this exercise is to detect subjects on the
property who should not be there. In
this case, thermal is the clear winner.