What are some really strange optical illusions

Optical illusion

Oddities, visual effects
and optical illusions

Gravitational anomalies,
an optical illusion!

This forest on the Kornberg in the Fichtelgebirge is apparently just as sloping, but with trees it seems less strange, maybe the wind could ...

Here you will also find the explanation of a phenomenon with which people are repeatedly fooled by making vehicles or bottles seemingly roll uphill: Gravitational Anomalies - Gravity Anomalies

The leaning tower of Pisa

Admittedly, these pictures are nothing new and the Leaning Tower of Pisa is really crooked. But every day wallow in Pisa in TuscanyPhotographers in the grass and ordinary people make the weirdest contortions to portray a giant preventing the Leaning Tower of Pisa from falling over.
Photos: Janis and Erwin Purucker

Pyramids on the beach of the Mediterranean?

It's a matter of perspective

Even the ancient Egyptians are amazed:
Such a large sand pyramid built by two and a half people in an hour! (No photo montage! Explanation)
Photo: Tobias Zitzlsberger, Sebastian Stochniol

If we are standing on the beach in the picture above, our eyes will not be fooled. That's why we have two of them. Through the spatial three-dimensional vision, we notice automatically that the pyramid is much closer than the people and estimate the size correctly.

Intuitively correct perception

Even in two-dimensional pictures, deception is not so easy: Our brain knows from experience that the trees in the picture below are no higher than the Nuremberg telecommunications tower and unconsciously classifies it correctly. In the picture on the right, too, we can automatically correctly assess the proportions between high-voltage pylons, residential buildings and television towers without thinking too much about it. The "thinking" required for this is only the application of experience, and we can do that in the subconscious.

If the television tower were a model on the top of the hill, we would be fooled and assume it was big and far away in the photo, because that would be unusual!

This picture shows the inside of the observation tower on the Großer Kornberg in the Fichtelgebirge. The arrangement of the stairs is not a photomontage. The only manipulation I removed was the railing. This causes the eye to lose its orientation.

At first glance, you might think that the stairs on the left lead up, but then you can't go any further. If you assume that you go down to the left and the staircase is photographed from above, it makes more sense.

After the page has fully loaded, you can fade in the railing by moving the mouse over it and then you can see that you have made a thorough mistake!

Confusing stairwells

Light, dark, or "different"?

A swastika was walled in with dark stones in the ➜ Bridge of German Unity in Rudolphstein. An attempt was made to destroy the figure by replacing four stones with bright ones.

However, the brain does not think dark = figure, light = background, but light and uniform = background, everything that is different = figure, and complements the well-known figure again, because the new stones are light, but "different".

but no deception

In between times no optical illusion, also no photo montage or digital trickery. Just a little joke:

Classified ad:

Do you have good comprehensive insurance?
I offer you a night for your car in my double garage as a special offer.
Total loss guaranteed!
Prepayment required.

The photo was taken in the Kyffhäuser Mountains below the ➜ Barbarossa monument.

The blind spot

The following is a demonstration of the "blind spot" in our eyes. The place where the optic nerve enters the retina is blind. The point is on the right in the field of vision for the right eye and on the left for the left eye. At this point we normally use the visual information of the other eye or, when this is closed, the eye and brain inconspicuously fill the area with what is seen from the outside.

Close your left eye and look at the "o". You can still see the "x" in the field of view. If you now change the distance to the screen, the x disappears at a certain distance (do not take your eyes off the "o" and only perceive the "x" in the field of view!). The left eye is reversed analogously. (Source: My biology class in 1968)

Confusion in the brain

Right is also not actually an optical illusion, but a psychological phenomenon, a demonstration of the conflict between the two halves of the brain.

The right hemisphere tries to say the colors, the left insists on reading the words. The phenomenon will too Stroop interference or Stroop effect named after J. Ridley Stroop, who used it in 1935 to determine the individual tendency to interference in the so-called. Color word interference to eat.

Read the color in turn
of the words, not the words!


Original and fake

The idea didn't come from me. Somebody told me about it once and later I experimented a little with image editing software. That's what came out of it. In the case of newer euro coins, the shape of Scandinavia has been changed in such a way that it can no longer be confused with the known body part! Have you noticed?

Hidden in the hidden object

Of course, no optical illusion again, of course, but fun that I couldn't resist:

Counterfeit 2 euro coins in circulation!

Timo's optical illusion

Do you also know such three-dimensional figures that, when executed as two-dimensional drawings, can be seen in two ways? You can practically "switch" the point of view. I discovered this as a child because a wall hanging on the wall behind my bed had a pattern that made this possible. The eyes only see the two-dimensional representation, our brain turns it into the spatial object. And you can influence this idea.

I received the picture on the right from Marin Muresan. Her son Timothy Muresan from Schömberg near Calw drew it when he was 8 years old. Depending on how you look at it, you think you are looking into a cylindrical cavity made of rings on the left, which extends to the right behind, or on the right to the left behind. Scientists call such effects Bistable perceptionor Multi-stable perception.

Mysterious puzzle

The parts of the same color are actually absolutely the same. If you cut them out and put them together in both ways, a hole is created! It is not due to inaccuracies in drawing or cutting out.

How can that be ?!

I received an old version of the drawing from Timo M.
(I know the e-mail)

Current graphic: Erwin Purucker


Movement where there is none!

Look at the point in the middle and move your head back and forth!

A similar graphic (below) where you only have to move your eyes are those Rotating snakes(rotating snakes) by Akiyoshi Kitaoka. See his website for more examples. The effect is created by unconscious small eye movements that each of us makes constantly, in connection with the asymmetrical color differences of the small elements (Figure released according to Wikipedia).

The waterfall effect

Please wait until the spirals start moving, some browsers only do this after the page has completely loaded.

Look at the center of the spirals for about 20 seconds and then look at another object, such as the back of your hand, and you will see that object flex and stretch for a few seconds.

Our eyes do not send the images to the brain, but process them. They only pass on what they consider important and useful. In this way they try to compensate for the rotary movement and only notice with a delay that the movement has stopped. Therefore the apparent movements after looking away are also opposite to the original ones.

These Movement aftermathwas first named in the early 19th century by R. Addams Waterfall effectdescribed because he was staring at a waterfall and then at another spot.

Negative images

Look at the four dots in the middle of the circle for a good 30 seconds, then close your eyes and tilt your head back a little.

You see the circle - close your eyes, after a while you see something in the circle ...

According to another instruction, you should also close your eyes after the 30 seconds, but then turn your head, look at a white wall and possibly wink your eyes. Both work for me.

I received the drawing from Eris Jones

The Troxler Effect

Look at the point in the middle ...

(Bend pretty close to the monitor and don't move your eyes!)

... after a while the gray disappears!

This disappearance of the same diffuse objects is called the Troxler effect. Staring at the point prevents the constant involuntary and imperceptible tiny eye movements that one does too Microsaccades is called. As a result, the same, blurred objects around the center of sharp vision are faded out after a short time.

Viewed from near and far

A skull?

Touch (don't click!) It with the mouse pointer and you will see what it is.
Without JavaScript or a mouseplease click or tap on it.

The original idea for this picture probably came from a drawing by
Charles Allan Gilbert, All is Vanity (1891).

The band Def Leppard ( CDs) had it modified a little and used it
as a cover for the CD Retro Active.

Sigmund Freud and sex

What do men have on their mind?
Of course, naked women!

The left drawing shows Sigmund Freud,who dealt extensively with it - which was evidently reflected in his facial features!

I received the drawing from Christian Bösch

I received this picture from
Patrick Mackaaij

Sandro Del Prete

Sigmund Freud would love the picture on the right.

I could hardly imagine it right away, but children were supposedly only supposed to see dolphins here!

Many letters have now confirmed that even small children see lovers first nowadays. It may be that it was different a hundred years ago, today such images are so ubiquitous that they are not uncommon even for small children.

Thanks to Roman Kriesten for researching the artist

Books on the work of Sandro Del Prete
Here you will find pictures and decorative items with
Optical illusions

(Fig .: advertising material)

Relative brightness

Fields A and B are actually the same color in the picture.
The eye interprets the shadow and tells us that the color must actually be lighter.

If you don't believe it, please press the "Animation on" button. An animation will make it clearer.

I became aware of the effect through a graphic by Hendrik
Animated graphics: Erwin Purucker

The two illusions above and below go back to the French chemistEugène Chevreulwho devised another theory of color in the 19th century after Isaac Newton and Johann Wolfgang von Goethe. The picture above is created by increasing the contrast in the eye with adjacent surfaces. In the case of adjacent gray tones, the darker one appears darker than it is, and the lighter one appears lighter. He called that Simultaneous contrast enhancement.

Aftermath in complementary color

He named the effect belowSuccessive contrastwhich describes the aftereffect in the complementary color after looking at a certain color area for a long time.

Stare at the red point in the middle of the US flag for half a minute, then at the red point in the middle of the white area below, after a few seconds you will see the original colors.

Cyan (light green-blue) and yellow are the complementary colors of red and blue. The eye becomes saturated with the former, so that one sees the others after turning one's gaze. This is also called a Afterimage effect.

I received the graphics from Slavko Brkic.

I received the picture from Rico

Black spots where there are none!

How many dark spots do you see?

This effect is a further development of the Hermann grid according to Ludimar Hermann (1838 - 1914) or Hering grid according to Ewald Hering (1834 - 1918). One calls the graphic Scintillation Gridafter Jim R. Bergen or Scintillating gridafter Elke and Bernd Lingelbach and Michael Schrauf.

(Freely based on Walter H. Ehrenstein Jr. and Bernd Lingelbach in "Physics in Our Time" No. 6/2002)

Vertical and horizontal by eye?

Angular illusion: crooked or straight?

Of course, none of the figures are as crooked as they look!

Tilt pictures, tilt figures

Spiral or concentric circles?

Look carefully, it is different from what you think!


old - young - old ...

(Please wait until the image moves, with some browsers this only happens after the page has fully loaded.)

Moving GIF: Erwin Purucker

Old Man Muffaroo

This island with the Old Man Muffaroois an image from a double-sided cartoon by Gustave Verbeek(1867 - 1937).
Turned upside down you can see a huge bird that "Little Lady Lovekins"has in its beak.

There are 3 options: Either you turn your monitor over, or they do a handstand, or they click here,then it works automatically.

A smiling lady ??

If you don't want to contort your neck, touch Hover (do not click) the image to flip it (JavaScript).

Without JavaScript or a mouse please click on it.

I received the picture from . It is the title page of the book "Savoir apprendre: les nouvelles méthodes" by Goéry Delacôte.
You can order it here at www.amazon.fr.
Unfortunately, I don't know what the book is about - can't speak French (: - ((


Impossible objects

6 graphics:
The first and arguably most famous object is the impossible triangle in the top left, too Tribarcalled. The Swedish artist Oscar Reutersvärdinvented it in 1934. The mathematician Roger Penrose also presented it as his invention. Since then it has also been called Penrose triangle.

Richard Gregorydesigned many such figures that make no sense in the spatial imagination and especially those that create strange optical effects when moving.

The Dutch artist M. C. Escher( Books) used the impossible basic figures for his pictures, especially woodcuts, lithographs and etchings, of impossible stairs and buildings.

The previously common term Puzzleshas almost been forgotten.

The picture on the right is from David Macdonald and is called The terrace.

It is similar to the picture "The curved chessboard" by Sandro Del-Prete.

Thanks for the permission to publish!

Alfons Krolage
made a tribar.
To enlarge the picture
please click this!

Photo received from Felix Kehl

A similar object with a detailed explanation
can be found at Wikipedia.

I received these two pictures from Patrick Mackaaij

M. C. Escher

One of the most famous pictures by M. C. Escher is this lithograph The waterfall.

Would that be nice: A ➜ perpetual motion machine that generates infinite, environmentally friendly and renewable energy. Even before everyone was talking about the greenhouse effect, people dreamed of it.

The forerunners of today's cinema are very simple blocks of paper that you slide through your fingers: Flip books, new German as Flip charts which are mainly used today for a wide variety of office applications and presentations, such as the table flipcharts for setting up www.schlenderringmappen.de.

Many artists have made use of the fact that our eyes do not always reflect what is seen objectively. Examples on my special pages:

René Magritte
For his picture Le Blanc-Seing(The blanket power of attorney) he used an effect similar to that of the elephant above.

You can find pictures as wall decorations and decorative items here: René Magritte

Salvador Dali
His picture Swans mirror elephants,
that he painted in 1937 is reminiscent of something
the Metamorphosesby M. C. Escher

Pictures as wall decorations and decorative items
you'll find here: Salvador Dali

M. C. Escher

In his picture Up and down stairs, a lithograph from 1960, he uses the one by L. S.Penrose, the father of mathematician Roger Penrose, discovered the effect of the infinite staircase.

Pictures as wall decorations and decorative items
you'll find here: M. C. Escher
Probably no optical illusion,
but a very controversial picture
with many secrets:
Leonardo da Vinci's Last Supper

More on my side
Leonardo da Vinci

Pictures as wall decorations and decorative items
you'll find here: Leonardo da Vinci
Also no optical illusion, but you can't believe your eyes:

The wife of Jesus Christ on old paintings!

More on my side Mary Magdalene.

Photo: Erwin Purucker

The world and God
no optical,
but a delusion?

Visit my site
"Physics, Religion and God":
my world view

Did you like my little website?
Maybe you will think of me when you need a book, a CD-ROM, a music CD or a video (maybe as a gift?). If you to your orders go through my websites, you can help mine Panopticon to expand further. You can use one of the search fields, visit my book corner, or maybe you will find something suitable on one of my pages. If you want to order something at a later date, maybe I could persuade you to take a detour via mine Panopticon to take. Please bookmark (favorites) so that you can easily find me again!

How about a book or CD-ROM on the subject? Maybe as a gift?


Framed pictures, art prints, posters and decorative items,

an eye-catcher for every apartment or public building,
with the most diverse motifs can be found here.
Below on suitable themes and artists: