Every now and then an image appears online which has people heartily debating its authenticity, arguing about its colour or asking how it came about in the first place.
There are also some amazing pictures that look like one thing but turn out to be something quite different.
We’ve gathered together a collection of the best from around the internet - pictures that’ll have you scratching your head, questioning your eyesight and generally feeling perplexed by their existence.
Different coloured creatures
Over on Twitter,David Novick, Professor of Engineering Education and Leadership, at the University of Texas at El Paso has been sharing a number of interesting optical illusions.
Including this one that seemingly shows green cats and pink dogs, yet in reality, both animals are the same colour. It’s the horizontal lines that are tricking your eye. If you zoom in closely and look at a small part of each animal you’ll see they are the same colour.
Floating roof
We’re not sure what’s going on here, but it looks like the roof of this truck is floating above the ground and casting a shadow on the stones below as well. How?
This only looks normal upside down
This photo of Elon Musk seems normal enough, apart from being the wrong way up. The thing is if you try to look at it the right way around you’ll soon find it’s not right at all.
An expanding dark mist
Self-proclaimed experimental psychologistAkiyoshi Kitaokastudies optical illusions and posts the most interesting ones over on Twitter.
Those illusions include the likes of this one which seems to show an expanding black mist emanating from the middle.
The four-eyed man
This illusion really messes with our eyes and his too apparently.
As far as optical illusions go, this one is both simple and painful. Who thought two pairs of eyes and two mouths would be enough to break your brain and make it painful to focus?
Reflections on the water
Less of an optical illusion and more of a brilliant bit of artwork. This is a mural that was painted on the side of a building, but intentionally painted the wrong way up so it reflected the correct way on the waters nearby.
Floating speaker
This photograph taken on the beach seems to show the speaker on a floating platform. No doubt down to our brain interpreting the shadow of the flag blowing in the wind as the shadow of the speaker’s platform and microphone instead.
Another classic illusion caused by our brains trying to decipher the scene before us.
Duck or Rabbit
This optical illusion has taken on many different forms since it first found its way into publication in the book “Philosophical investigations” by Ludwig Wittgenstein in 1953.
Here it is suggested that there are ambiguous images that can be seen in two (or more) different ways.
In this instance, the drawing could be a rabbit or a duck or both and what you see first will be down to your perception of the world or based solely on suggestion - the duck and rabbit axis in this version make it easier to quickly decipher both variations.
Ambiguous cylinder illusion
One of the finalists for the “Best Illusion of the Year Contest” makes for pretty mind-bending viewing.
Here Kokichi Sugihara places a set of cylinders in front of a mirror. The reflection shows a different shape until the object is revolved and then we see the opposite. It’s best viewedinthis video.
If you’re left scratching your head after watching that video, you can seea breakdown of how it works here.
Wonderfully weird greyscale store
While out shopping, YouTuber Holly McKee discovereda real-life optical illusion. Nestled away in the children’s clothing section she discovered an aisle of black and white clothes that made the photo look like a filter had been applied.
When peopleon Twitterdoubted the image wasn’t edited, shetook to YouTube to prove them wrong.
