Did you know: Motion Dazzle – The Puzzle of Black and White
Motion dazzle describes high-contrast patterns (e.g. zigzags on snakes and dazzle paint on World War I ships) that do not conceal an object, but inhibit an observer’s perception of its motion. However, there is limited evidence for this phenomenon.
Have you ever wondered why a zebra has stripes? While even scientists don’t know the causes for sure, they have great reason to believe it has something to do with insect bites from bugs which are carriers of potentially fatal diseases. They conducted experiments, in a large open field by taking zebras, horses covered with stripes, and uncovered horses.
While the fly-clusters hovering over the animals were of similar sizes, a closer analysis resulted in the observation that the flies landed on the zebras at an average of one-fourth of the rate they landed on the uncovered horses. Moreover, a recent similar study was conducted on human mannequins, where they found a similar result – these stripes deter flies from landing on one’s body. But, why so?
A possible hypothesis is – disruptive colouration, where the goal is to confuse, but not conceal. This leads to the disruption of the outline of their body, using colours which strongly contrast with each other..and this hypothesis led to the birth of “razzle-dazzle” or “dazzle camouflage”.
Ships painted with dazzle camouflage (Click on image to visit source)
The idea was to paint a juxtaposition of geometric shapes on ships using contrasting colours, to make it abstruse to approximate a target’s position, speed, and heading accurately, and hence increase the probability of misfire by the enemy. It was used during both the World Wars by the UK’s Royal fleet and the US Navy. Though there’s a caveat here – so many factors were involved during the wars, that it is impossible to determine which were important and whether this camouflage really dazzled the enemy ships. But either way, it makes for a fascinating fact.
To see this ‘confusion’ in action, one can try to experiment with the face-detection functionality now offered in most smartphone cameras, as I did. As you can see, the camera identifies the face and encloses it in a yellow square (left side), but when black stripes were painted over the face to contrast with the white skin of the person (right side), the camera ceases to do so. Let me know what you find in the comments section!
Please visit these links to know more:
https://en.wikipedia.org/wiki/Computer_vision_dazzle
https://publicdomainreview.org/collection/dazzle-ships
https://en.wikipedia.org/wiki/Dazzle_camouflage#World_War_II
Tags: biology
This is amazing. Very interesting to see that this could confuse the computer vision algorithms as well. Thanks for sharing!