Camouflage, human perception and ghillie suits

Our perception of objects and shapes is determined by the brain's organisation of the sensory information it receives from our surroundings. Due to the automatic, innate mechanisms that govern human perception, our brains are wired to perceive shapes and figures in contrast with the background. This is an evolutionary adaptation seen in many animal species, particularly social pack hunters like homo sapiens. Ghillie suits are so effective for concealment because they break up the outline of the human body and interfere with the image reconstruction process that enables us to recognise a human silhouette. 


A scientific explanation has been offered by Gestalt, one of the leading schools of experimental psychology. Gestaltists postulate that perception is the result of complex interactions among numerous stimuli, on the basis of which the brain generates a self-organised "global whole". This global whole is influenced by specific mechanisms of human perception that help explain how and why ghillie suits work. We begin with the fundamental principle of Gestalt perception.


Law of Emergence: also known as the Law of Prägnanz or Law of Good Gestalt, it states that perception of an object from the background depends on the object's relevance - that is to say, on the contrast between the object and the background. Where contrast is minimal, the object does not stand out from the background. Wearing a ghillie suit the same colour as the surrounding environment significantly reduces emergence and increases camouflage, as the figure will be perceived as part of a global whole, at one with the environment. 

Other principles come into play with the Law of Emergence.


Law of Similarity: visually similar elements tend to be perceived as a single unified group. This explains why, by emulating the colouring and haphazard shapes of the natural environment, the ghillie suit can blend almost perfectly into the surroundings and be perceived by the brain as an integral part of them. The camouflage effectiveness of raffia and sisal fibres is a clear example of this principle.

Law of Continuity: individual elements tend to be perceived as a whole when they are positioned in a continuous line with one another. This is exactly what happens when a ghillie suit is positioned next to a bush, on grassy turf or among fallen leaves.

The Gestalt approach to human perception helps us understand how ghillie suits interact with their surroundings, and provides remarkable insight into concealment strategies. Let's see a more direct example of our Gestalt-based approach.

Pictured below are 3 samples: a ProApto Greenzone in raffia, one in green jute and a handful of artificial leaves commonly used in leaf-suits. Which of these samples offers the best degree of concealment?  Some believe ghillie leaf-suits are superior to jute and raffia ghillies, but we disagree. If we take human sensory perception into account, a larger object surrounded by thinner shapes is more easily distinguishable than a slim object among similar shapes. The differing morphology and larger visual space occupied by the large object make it more easily detectable in contrast with the background. 

A leaf-suit, visually a collection of broad shapes, will be extremely effective in environments characterised by similar shapes (such as broad-leaved forests), but its efficacy will drastically decrease in grassy areas, leading to concealment issues. Conversely, a full raffia ghillie will work extremely well in a grassy environment, but offer poor concealment in a broad-leaved forest. However, it bears saying that raffia ghillies have higher versatility than leaf-suits, simply because grass is generally more present across environments than leaves and trees. Even lacking grass, thinner shapes such as twigs and shrivelled vegetation are found everywhere (with the exception of hot and cold deserts).

Below is a video example of jute's adaptability in different environments. In the following video, the same ghillie suit is used to cover a 13 km distance, moving from 1200mt to 2500mt of altitude. 

Jute is the intermediate step between thin and broad shapes. The multitude of strands falls into random, irregular shapes, making it a reliable material for concealment, especially during transitions between different environments: no other fibre can rival jute's versatility. Admittedly, jute will not perform as well as a leaf-suit in a broad-leaved environment, in the same manner as a raffia ghillie's effectiveness decreases outside of grassy environments, but it presents an adaptable compromise for camouflage concealment across large distances and seasons. The videos below were taken in a mixed environment, featuring a combination of thin and broad shapes. See for yourself how well jute, raffia and artificial foliage perform.


The following video showcases jute's versatility across 3 different environments, gaining +900mt of altitude for a total distance of 21 kilometres. It features 5 ghillie camouflage patterns and makes a performance comparison between jute ghillies, a full-raffia suit and a leaf-suit.

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The following images examine the effectiveness  of ProApto ghillie suits across different terrains. The key factor in a successful camouflaging system is adaptability across multiple environments. Neuropsychological studies on human perception of colours and shapes provided the basis for our designs and are the foundation of our products' excellent camouflage capacity.


Recommended reading:

Wagemans J., Elder J.H., Kubovy M., Palmer S.E., Peterson M.A., Singh M., von der Heydt R., A Century of Gestalt Psychology in Visual Perception I. Perceptual Grouping and Figure-Ground Organization. Psycholical Bullettin. 2012 November; 138(6): 1172-1217.
James J. Gibson, The Ecological Approach to Visual Perception. Psychology Press, 1986 by Taylor & Francis Group LLC.

Useful Linkhttps://www.sciencedirect.com/topics/neuroscience/gestalt-psychology


Recommended reading for laymen

https://en.wikipedia.org/wiki/Gestalt_psychology

https://en.wikipedia.org/wiki/Principles_of_grouping

https://en.wikipedia.org/wiki/Gestalt_psychology#Pr%C3%A4gnanz

https://www.youtube.com/watch?v=RWJSC1HU32c