“Camouflage” was not an existing word back in 1890 when the Darwinist-zoologists Sir Edward Poulton wrote his book ‘The Colours of Animals’. It was not yet a proper word even later in 1909 when Abbott Handerson Thayer wrote his controversial book entitled ‘Concealing-Coloration in the Animal Kingdom’. With a vocabulary more limited than now, Thayer’s work began by explaining how an otherwise, utterly conspicuous bird like the male peacock could veritably vanish inside a forest.
The Italian verb “camuffare” means to hide or disguise. The French verb “camoufler” similarly means to conceal or cover up – as a theater actor might apply makeup right before a performance. The French word “camouflet” is used as a noun perhaps to depict a snub or an insult or it might describe a crater in the ground caused by an underground explosive. Camouflet might be the smoke blown into someone’s face as a practical joke. The word “camouflage” is newer; possibly dreamed-up during the trench warfare of WWI, by some French infantryman as he lay freshly covered over with dirt excavated by nearby artillery bombardment. In the last century the definition of this new word camouflage, has swelled to include many types of deception to the eye or subliminal trick to the brain.
The concept of camouflage is very old. Mother Nature itself is resplendent with convincing examples of camouflage. Both below the water or above, most predators and prey alike participate in the masquerade of visual deception. Even plants play the game. Some plants deliberately attract while others can effectively repel pollinators or herbivores with their looks alone. Thousands of years ago aboriginal hunters might have been the first humans to use camouflage, if they wore animal skins as a disguise to hunt game. From time immemorial camouflage has proven to be a very advantageous survival tool for a great many living things. It will continue to be so tomorrow. Mankind today being no exception, has need to hide from himself.
Why does it work?
Not all “camo” is good camouflage. Some military camo is really poor. At best even the majority of nature’s camouflage schemes are specialized or static and so will succeed only for a limited set of circumstances. Some fish, chameleons, squids and octopuses though are luckily equipped with the ability to dynamically change their disguises. Chromatophores present in their skins empower this magical ability.
Color is certainly not the only important component of successful camouflage. With humans in fact, color-blind individuals have been actively sought for as airborne artillery spotters or as snipers by the military, specifically because they are not distracted or fooled by colors. These people with unusual red-green color receptors in their eyes may be better equipped to see certain underlying contrast that outline the shape of a threat. Though color is still important to the average eye, any eye can still be led astray by other, more subtle mechanisms. Mechanisms, some of which to be explained shortly.
Sophisticated modern optics and hypersensitive sensors are being exploited on the battlefields now. Effective military camouflage schemes today and in the future will need to work for a broader electromagnetic spectrum, which means masquerading even in non-visible light.
Contemporary with the Napoleonic Wars, military uniforms were usually bright and colorful. The British and Danish armies were fond of red coats, the Spanish, Austrian and Saxon armies favored bright white or light gray, the Poles, Prussians and Napoleonic French wore dark blue colors and the Russians wore green. The arrival of more accurate firearms with longer reach due to the rifling of barrels, changed that. By the time of WWI most progressive armies had switched to low visibility clothing and soldiers were now hiding behind objects for protection rather than standing starkly out in the open.
To be sure there were some isolated incidences of soldiers wearing camouflage well before WWI. For example Rogers Rangers who participated in the French Indian Wars, wore uniforms that were dyed green. The French led Wabanaki Confederacy natives that they opposed, wore deerskin if anything and were harder to see. On the other side of the planet and around 1846 a British officer of an Indian Army regiment had his whole troop go down to the river and rub mud into their new white cotton uniforms. Later still and on yet another continent the first “gillie suits” for snipers were used by Scottish soldiers fighting in the Boer Wars of South Africa, a decade before WWI.
<Expandable Thumbnails follow> the “tiger-stripe” camouflage worn during the Vietnam War provided good concealment in the jungle. The French introduced the pattern. The American uniform versions were great at first but due to faulty dyeing processes – would fade badly after a laundry wash.
The coat below would work as camouflage in a room full of steaks.
Below is an example of bad camouflage. It’s a three color patten of shapes with a tiny scale. The uniforms must look like homogeneous pea soup from a distance.
Any notion that one camouflage can be appropriate in many different environments is a preposterous proposition. Nonetheless this silly one-for-all camo notion continues to be funded, researched and tested. The reason is that an organization like the Army, or any other branch of military service, works as a team. Basic military psychology dictates that members of a team should look and dress alike. Each of the individual services wants a new, modern, high tech look. Outfitting hundreds of thousands of soldiers with four or five sets of new uniforms and accouterments soon gets to be very expensive. In 2004 the US Department of Defense spent $5 billion to outfit the Army with a new pattern of camouflage uniforms. Then the Army decided they didn’t like it.
The computerized, digitized, scientifically analyzed UCP (Universal Camouflage Pattern) adopted by the US Army a few years ago is a prime example of a camouflage flop. Some fundamental design considerations were ignored. The omission of black was a stupid decision. The pale, cement colored, pixelated UPC could only look natural for someone standing inside a rock quarry. The Army might have been wiser to stick with solid, century old khaki, olive drab or feldgrau colors.
There is nothing wrong with pixelated patterns but don’t buy into the gimmick that computers can make camo planning decisions. UPC was a three color camo scheme where the contrast was too insubstantial. Additionally the scale of the contrasting regions was too small within UCP. Most camouflaged uniforms though, mistakenly use too small a scale of pattern. There is little need to deceive the enemy’s eye at close up range, but greater need to fool it at rifle or battlefield range (300 meters). The chunks of contrasting colors need to be much larger to affect an observer from distance.
There is still great room for improvement in the world of military camouflage and it is a realm where the psychologist with discretionary artistic skills can still innovate. No doubt there are as yet, still undiscovered and inventive ways to lead the eyes astray.
It is from nature that mankind gets his camouflage ideas. In nature you find both plants and animals exploiting cryptic coloration to hide or mimicry to impersonate something else. Some of the flowering plants (especially some orchids) practice a highly developed mimicry. The intent is usually to attract bees, wasp or flies to assist in pollination.
< * Of the many borrowed photographs to follow: first, they have been declared to be of public domain; second, wherever possible an effort has been made to embed attribution and source metadata into each JPEG photo – should it be examined or downloaded. >
As if the imitation of a stick isn’t good enough, the phasmid below also carries its tail higher than his head, offering a less crucial first target to a predator.
The phenomenon of countershading went unappreciated until about a century ago when the naturalist and artist named Abbott Thayer (who painted the peacock mentioned earlier) first identified this mechanism. Thayer noticed that many animals have a dark upper body but a lighter underbelly. He reasoned, that these animals when illuminated by sunlight from above have their overall appearance flatted or dulled rather than accentuated.
Disruptive coloration and alternating shapes in camouflage attempt to visually scramble the contour or outline of a subject. A net thrown over an artillery piece interrupts or breaks up the outline of the cannon. A disruptive eye mask or eyestripes on many an animal helps disguise its vulnerable, usually dark and distinctive eyes. Shapes or patterns that are distractive enough will lead the eye away from the edges or outline of a form. The coloration in these disruptive patterns are often strongly and abruptly contrasted. Symmetry is carefully avoided, because animal brains are wired to notice spatial correspondence.
Notice the semi-circles created by contrasting light – against dark bands on this viper below. Notice how the markings run perpendicular or counter-intuitive to the body’s axis. These markings disrupt quick interpretation of the viper’s contour by offering a more attention getting alternative for the viewer’s eye.
Below, notice the direction of the disruptive stripes on the legs.
Cubism and Dazzle camouflage
A noteworthy art movement beginning at the dawn of the 20th century was known as “Cubism”. With cubism the art does not necessarily try to make a 2-dimensional canvas look 3D, but it does attempt to depict a subject from multiple viewpoints. In cubism the elements of a subject are broken up and are then reassembled in an abstract form. (*The following examples of cubism are declared public domain by virtue of their old age – which here exceeds 75 years).
The stark designs put on ships beginning with WWI are known as “dazzle camouflage” and have roots or kindred elements with cubist art. The purpose of dazzle camouflage was not to conceal a ship, but to foil an enemy’s attempts to accurately calculate its range, heading or speed using optical observations. The original “dazzle” as credited to British artist Norman Wilkinson was very blunt, to serve a purpose. Later the term would be applied to every type of concealing paint job on put a ship, whether that resembled cubism or not.
Below the dazzle pattern helps foil a potential torpedo’s firing solution by misdirection of the ship’s actual heading.
* In the 1860’s the state of the art for aiming a large cannon was to look down the barrel and fire point blank. In following decades, longer shots at sea were accomplished by guessing a range and then elevating the barrel beforehand while waiting for the sea swell to bring the target into the aim of pre-adjusted iron sights. Concurrent with the Spanish American War, ships began to be equipped with optical rangefinders invented by Admiral Bradley Allen Fiske. His stadimeter was a handheld device that looked similar to a sextant and which would later be incorporated into almost all submarine periscopes. Versions of his coincidence rangefinder that worked by triangulation and trigonometry would quickly find their way into all warships and land based artillery units. Radar (RAdio Detection And Ranging) was still in its infancy at the beginning of WW2. In a few short years radars were incorporated or retrofitted into the latest British and American fire control systems aboard ships. At first radar just augmented either the huge (long baseline) coincidence or stereoscopic type optical rangefinders.
In WWII the paint jobs on ships were looking very different, but the name dazzle still stuck. The famous German battlecruiser Scharnhorst shown above right mimics a smaller, less threatening ship from a distance.
In the split picture below an unknown warship hides against the bank or cliff side. The battleship Tirpitz (sister ship to the Bismarck) spent much of the war hiding in such a way. The cruiser on the right side has a bow wave painted on its front, making it appear to be traveling much faster than it might be.
The catchall “dazzle camouflage” phrase is still being applied to some new warships and face paints today.
The once very popular Argus C3 camera used a stereoscopic rangefinder to focus its lens. Cameras with SLR (Single Lens Reflex) mechanisms would eventually overtake the rangefinder sort, a possible advantage being superior performance at close up distances.
Yet another version of dazzle is CV Dazzle, created by artist Adam Harvey. CV stands for Computer Vision and his concern is resisting the quickly growing surveillance state that tracks people’s moment with digital cameras and facial recognition software. The anonymous people behind this intrusive surveillance, be they law enforcement or employees of a private company – just take what imagery they want without asking. Facial recognition software has grown quite sophisticated recently. Analyzing how these algorithms work so that they might be countered or thwarted might be good subject mater for a future post.
* Now that some established examples of camouflage have been shown and the topic outlined a bit; it comes time to introduce some ideas that might improve new camouflage schemes for the future...
Op Art (or Optical Art) uses optical illusions. Op Art is abstract, employing perhaps only black and white lines to create an impression of movement or to conceal another image. Some optical illusions can occur without man’s help, when our physical environment can distort what we perceive, perhaps by bending light. Atmospheric conditions might be responsible for mirages, for the moon to seem bigger than it should, for far away mountains to appear closer than they really are or for a straight stick to appear bent when you see part of it dip below the surface of water. Another category of distortions, ambiguities and paradoxes of perception can be caused by physiological activity in the retina of one’s eye. Afterimages that might linger in one’s vision after he looks away from a high contrast image is an example of physiological optical illusion which is caused by photochemical activity in the retina. In the so-called “Hermann grid illusion” (from German physiologist, Ludimar Hermann /1870) a person probably senses black dots where they don’t exist – because the separate light and dark receptors of the eye are scrambled and are competing with each other for attention.
The most common types of optical illusions may involve neither biology of the eye nor altered perceptions caused by natural environmental factors. Instead, because of the way the human brain is connected and conditioned it is capable of making very quick assumptions and then of sometimes jumping to false conclusions.
“Impossible objects” are two-dimensional figures that can be subconsciously interpreted as three-dimensional objects. Impossible objects are not physically rational but they can be drawn. The ‘Penrose stairs’ and the ‘Impossible Triangle’ shown above were both originally thought up and published by a British psychiatrist and his physicist son in the 1950’s. The Dutch graphics artist M.C. Escher would later incorporate the impossible staircase into some of his work.
Geometrical illusions would appear to distort reality when they actually don’t. Many are named for the physiologist or psychiatrist who originally created them. Some simple examples would include the Müller-Lyer illusion, the Hering illusion, the Zollner illusion, and the shifted-chessboard illusion originated by German-American psychologist Hugo Münsterberg. Completely different but still a “geometrical illusion” is the checkerboard illusion (and here is a dynamic HTML version) .
Ambiguous illusions can offer more than one valid perception or interpretation. The “Necker cube” is an old ambiguous illusion that dates back to 1832 and a Swiss crystallographer (someone who studies atomic arrangements in crystalline solids) by that name. Around 1915 the Danish psychologist Edgar Rubin created the first ambiguous or reversing two-dimensional form to be called – a “Rubin’s vase”. Four such vases are shown below.
Hybrid illusions can be perceived in more than one way, depending upon viewing distance. These illusions can be created by superimposing blurred elements of different photographs over one another. The technique was originally proposed by Aude Olivia and Philippe Schyns in 1994. One image dominates up close but another takes over as you step back.
Shadowing plays a very important role in “peripheral drift illusions“. Reversing the shadowing reverses the rotation of drift. Strong contrast, blinking, eye movement, peripheral vision and the brain’s perceptual processing contribute to the illusionary sensation of motion. The almost famous “rotating snakes” image below was copyrighted in 2003 by Akiyoshi KITAOKA, Professor, Department of Psychology, Ritsumeikan University, Kyoto, Japan. The professor has drawn many other illusions which are also displayed on his website.
Working with similar tricks, the false spiral or twisted cord illusion does not appear to move. In 1908 a British psychologist named Sir James Fraser drew the first false spiral, where the arcs are actually a series of concentric circles.
Pinna’s Intertwining Illusion is a derivative of the twisted cord illusion.
* Only a few methods of optical illusion have been shown here. These toy with either physiologic or psychological mechanism. One can better now hopefully perceive, how optical illusions when incorporated into camouflage patterns – might help enhance the disruptive affect of those patterns.
Holography, Lenticular lenses, Agamographs & Stereoscopy
Real holograms reproduce very realistic 3D renderings of objects but both the recording and the viewing require laser light. The hologram itself is a surface profile of the light field surrounding an object. There are some techniques available to mimic the 3D effect of holograms though. Lenticular lenses for instance are glass or plastic lenses, textured with ridges or rows of bumps. In lenticular printing, two or more images are interlaced together on a paper or substrate and then bonded to the base of the lenticular lens. Either the result looks 3-dimensional or a separate image altogether appears when the viewer observes from a different angle.
Working on a similar principle as the lenticular lens are “Agamographs” which are named after a noteworthy artist named Yaacov Agam. While Agam made sculptures or artworks from various materials, anyone can create a facsimile of a 3D image by folding paper in a special way and painting segments of different stereo images on alternating folds.
Stereoscopy is stereoscopic imagining and there are a few different ways to do that. Stereoscopes are the contraptions that you look into to see a three dimensional image with realistic depth. The left and right eye are segregated to see slightly different vantage points of the same object and then the brain’s visual cortex combines the binocular disparities to produce depth perception. A typical stereograph consist of two photographs that were taken simultaneously by a special camera that uses two lenses and two sets of film. A “stereogram” once meant the same as stereograph. Now however stereogram is synonymous with “autostereogram” – which is a single 2D image that can be perceived as a 3D image, without the help of a stereoscope or use of two images.
Autostereograms depend upon the difference or binocular disparity between two good eyes to create a 3D impression. Computer software is used to map depth coordinates obtained from one form – to the surface of another image. Some of the pixels of the surface image are shifted according to the depth of the hidden form. Most autostereograms are intended to be viewed by means of “wall-eyed convergence”, which means the viewer stares through the graphic, not crossing his eyes. Visual neuroscientist Christopher W. Tyler with the help of a computer programmer, created the first autostereograms in 1979. However a simpler form of random-dot stereogram technique was being discussed 60 years before that.
Projection and Perspective
It could be mentioned that for artwork or mechanical drafting, there are many ways to project a three-dimensional object onto a two-dimensional surface. First, a 3D projection will have lines of sight or projection lines that are either in perspective or are in parallel. Perspective in a drawing is where lines converge or skew towards one or more vanishing points. The lines of parallel projections however, don’t converge into the distance. Oblique projections slant or slope and have no perpendicular nor parallel relationship with any line or plane surface. Axonometric projections have lines of sight that are perpendicular to the plane of projection. Axonometric drawings also have edges or axes that are measured to scale but any curves or diagonals will be optically distorted.
When architects or engineers want to whip out a quick sketch of a building or object they might resort to a simple parallel/axonometric drawing known as an isometric projection. The angles in isometric projections are all multiples of 30 degrees. A draftsman that still knows how to hold a pencil might use a drawing aid known as a 30-60-90 set square, or might sketch on isometric graph paper where the lines are already marked. Less often used, dimetric and trimetric projections look similar to isometric axonometric projections but use different angles.
In previous decades the thermal imaging night vision equipment that soldiers might have used, worked within the invisible long wavelength infrared (LWIR) or mid wavelength infrared (MWIR) spectrum. These worked by reading the heat emitted by the object itself. Today’s higher generation / newer tech night vision equipment though, uses the ambient IR sent from very distant stars.
These newer night optics predominately rely upon lower wavelengths and higher frequencies; either from the short wavelength infrared (SWIR) or near infrared (NIR) spectrums. These optics produce high resolution images by reading absorption characteristics returned from a target.
Different substances have different IR absorption characteristics. There are many materials that absorb IR, less that reflect IR, some that are transparent to IR and even some materials under development for the influence they might have on infrared light. Some textiles, nets and miscellaneous surfaces used by the military, already dabble with coatings intended to affect visibility in the IR spectrum.
There has been some real research done and authentic videos showing how invisibility cloaks could work, but also some false videos about invisibility cloaks – using Hollywood style “blue screen” techniques and video editing software. The authentic research has a long way to go before the technology could ever be used in a camouflaged suit however.
The invisibility videos that are honest, must still be carefully staged. The demonstration or illusion if you prefer requires a computer, a video camera, a retro-reflective material, a projector, an iris diaphragm and a beam splitter. Typically a person stands behind a blanket of special fabric and you think you can see through him; because a camera is filming the scene behind him as a projector puts that same image on the blanket. The smaller details are complicated.
Metamaterials that can bend light are under development too. These also have a long way to go before becoming physically practical as a means of concealment.
In the slideshow that follows a prospective pattern using some isometric angles and a few circles, was quickly colored in using four colors. Ostensibly for painting something small like a toolbox. The original intention was to study how difficult it would be to design a pattern which would comfortably replicate itself over a larger area, once its stencils were moved adjacently up or down or sideways. Not an elementary task. Considering that the base-coat of an item will already be of one color, only 3 stencils would need to be cut out with an X-Acto knife. This is just a disposable example. The components are a bit too numerous and sometimes too close together to leave behind a sturdy stencil once the holes are cut out. After re-reading this post the last slide in the series features a little “disruptive shadowing”, added as an afterthought.