Feed Button
Description Presented here is a vast gallery of many different forms of Optical Illusions. Whether these optical illusions are conveyed through fractals, photographs, architecture, art, or old fashioned pen and ink, they are bound to remind you that "seeing is not believing."

Caution!!!! Some of the optical illusions on this blog may cause dizziness or possibly epileptic seizures. The latter happens when the brain can't handle the conflicting information from your two eyes. If you start feeling unwell when using this website, immediately cover one eye with your hand and then leave the page. Do not close your eyes because that can make the attack worse.
Fractal of the Day Fractal of the Day
Provided By Sprott's Fractal Gallery


Moon Optical Illusion

Have you noticed that when the full moon is close to the horizon that it appears larger than when it is high in the sky. This is known as "The Moon Illusion", I have heard of this illusion before but I hadn't thought about it in a while, that is until the last full moon.

I was driving up to my house early and I was absolutely amazed at how large the moon looked rising next to my house. I know that it wasn't any larger than normal but on this night the illusion was captivating.

Below is an excellent photo depicting this illusion.

Why does this happen?

Moonrise over the Lincoln Memorial

Moonrise over the Lincoln Memorial
Richard Nowitz/National Geographic
Buy this Framed Art Print at AllPosters.com

Before we talk about why this happens, I need to establish with you the fact that the moon is no larger on the horizon than it is high in the sky. If you actually measure the size of the moon at different points across the night sky you will find that there is no appreciable difference in the size of the moon through its path.

Take the below photo (Astronomy Picture of the Day) as evidence that the moon appears the same size no matter where it is in the sky.

Moonrise Over Seattle
Credit & Copyright: Shay Stephens

So why is this illusion so compelling? I think NASA sums up the current theories nicely when they say "After all these years, scientists still aren't sure why." Below is a list of sites that explain or debunk the various theories. I'll let you decide who might be right. I just plan on enjoying the view when I see the moon low on the horizon and leave the theorizing to others.
The Moon Illusion Explained -- According to Don McCready, a Professor Emeritus of Psychology at the University of Wisconsin, the Moon Illusion is caused by oculomotor micropsia/macropsia.
Summer Moon Illusion -- The lowest-hanging full moon in 18 years is going to play tricks on you this week.
The Moon Illusion: An Unsolved Mystery -- a nice overview of the Moon Illusion and its possible causes.
New Thoughts on Understanding the Moon Illusion -- from Carl J. Wenning, Physics Department, Illinois State University
Experiment in Perception: The Ponzo Illusion and the Moon Explaining the Moon Illusion -- from the Proceedings of the National Academy of Sciences

Continue reading the full article...


Optical Illusions in the Clouds

I believe that we have all looked up at the clouds at some point in our lives and seen images in the clouds. Some are clear as a bell, anyone could see the same thing you saw, or at least that is what you thought at the time. Since the clouds constantly change you usually don't have time to grab someone and drag them outside to see your Picasso in the sky.

Sometimes you are lucky and you are walking with a friend and point out the image that your creative eye caught only to be told that you are missing the big picture and if you look closer you'll see what your mate has cleverly detected.

With this phenomenon in mind I started searching the web for an appropriate picture that I could share here. I came across this photo on Talking to Spirit. I think this is a great photo to illustrate my point so I asked Pauline if I could use this image here.

Bears in the clouds optical illusions image

Clouds in Oakland, CA
© 2004 Pauline Evanosky
Used w/permission

What do you see in this image?

I see three teddy bears and one is a baby hanging on the back of its father. (I actually see five bears but three are prominent.)

Well friend here is your chance to point out the big picture that I may have been missing.

Continue reading the full article...


Thanksgiving Turkey Optical Illusion

This illusion makes the rounds every year. I can't take credit for this inventive cooking technique and since my wife and kids will be cooking for three homeless families at the church again this year I don't think experimenting with this technique would gain me any points.

However I know many of you are up early getting ready to put the bird in the oven. Although you love doing for your family, you look around and don't see them up at this time. You, men and women, are the perfect group to experiment with this technique and report back and let us know how it worked in real life.

Take a minute or two and apply the below techniques. Don't forget to snap the digital picture prior to carving.

Good Luck and have a Happy Thanksgiving :)

Thanksgiving Turkey optical illusions image

1. Cut out aluminum foil in desired shapes.
2. Arrange the turkey in the roasting pan, position the foil carefully
3. Roast according to your own recipes and serve.
4. Watch your guests' faces.

Continue reading the full article...


San Francisco Quake Optical Illusion

I lived in San Francisco area from 1983-87 and have many fond memories. I learned to drive a manual shift automobile, I met my wife, and I got married. My wife and I spent many a weekend in the city enjoying what this great city had to offer. While living in the Bay area we only experienced a minor quake or two, barely a rumble.

But on October 17th 1989 a magnitude 7.1 earthquake struck the Bay area just before the third game of the World Series at Candlestick Park. This was the worst earthquake since 1906, many buildings collapsed and many others shifted off of their foundations. This picture was taken after the quake.

How is it that this building is leaning so far over yet there is no apparent damage?

San Francisco Quake optical illusions image

© 2002 Erwin Purucker
Used w/permission

This is actually Erwin's daughter, thankfully she seems to have survived the shake in one piece.

Continue reading the full article...


Paradoxical Pavilion Optical Illusion

I featured this previously as the Student Union Optical Illusion. At the time I had no idea who had created this illusion. Since then I discovered that this illusion was created by Walter Wick for his book Optical Tricks.

Who is Walter Wick? You can check out his biography here. However if you have kids I'll bet you may already own a book or two that he has photographed or illustrated. That is if you have any of the I Spy series of books. It turns out I was a big fan of Walter Wick's work and didn't even know it. Click this link for Walter Wick's books @ Amazon.com

Long story short, I contacted Mr. Wick and asked permission to use this photo here on my blog. He was very gracious and has granted me permission to show this image here.

Going Up optical illusion

"Going Up?"
©Walter Wick, 1998
from Optical Tricks
Used w/permission

Mr. Wick took it one step further though and has allowed me to publish below exactly how he managed to create this optical illusion.

Like many optical illusions created to be photographed this one only looks complete when shot from one specific angle.

Anyone can digitally manipulate an image but few have the creative mind and patience needed to stage such an illusion. You can read Walter's comments on this illusion here.

Going Up optical illusion Revealed

"Going Up?" Revealed
©Walter Wick, 1998
from Optical Tricks
Used w/permission

Thank you Mr. Wick for your generosity in allowing me to post this here and as a parent I want to thank you for many hours of enjoyable time with my children trying to find all of the items in your I Spy books.

Continue reading the full article...


Young or Old Man Optical Illusion

What do you see?

Do your see a young cowboy looking into the distance or a image of the face of a time worn miner?

Leaning Tower of Pisa optical illusion

Continue reading the full article...


Metal Sculpture Optical Illusion

Sci-Art Bloggers Friday Favorites

I don't know what to make of this mechanical monstrosity. I don't know the origin of the piece, so I lack the who, what, when, where and why of this illusion.

If anyone can fill me in on the background of this image I would appreciate it.

Still I love the style of this creation.

Mechanical Structure optical illusions image

This is the Sci-Art bloggers Friday Favorites. The Sci-Art bloggers are a group of bloggers that frequently cover that area where art and science overlap.

Below are some postings from our members that I picked for today's Friday Favorites set.


Artsy Science "Retro Lab Stuff"
Bibi's Box "Books Illustrations on Blogs"
She Dreams in Digital "Animated Virtual Harmonograph"
What Is It? "This Weeks Photos"
The Daily Poligraf "Getting nearer"

As our group grows I will only put posts here that are submitted by the members. But until then enjoy some fascinating posts for this week.

Continue reading the full article...


Build This Optical Illusion Curio Shelf

curio shelf optical illusions imageDaria creator of stabilitybaby image

Last Friday, Nov 4th, I posted a Curio Shelf optical illusion and commented that it didn't look structurally sound. I had one viewer, Daria, comment as follows

"Actually, I can think of a scenario in which this would not only be possible, but provide for a stable shelf."

I appropriately bowed down to her obvious expertise. In response Daria of Step Step Build explained in the comments section how this shelf could be built.

I understood exactly how it was possible but she went a step beyond just telling me how it could be done. She modified the original image so you could see how it could be built, notice each bracket is constructed with 2 right angles and is actually 3 edges of a cube. Of course it would only look like this from one specific angle (in this case you would have be able to see through the wall or mount it on a clear glass partition).Stability Baby Book Shelve optical illusion revealed

I think it would be great to build this shelf, mount it on a glass wall then photograph it, frame the photo and mount the photo on a wall where guests could see it. I would then have the actual curio/book shelf in use, also where guests could see it.

I wonder how many would ask why this shelf was constructed oddly and how many guests would make the connection between the photo and the shelf?

Thanks Daria, very nice.

If you still don't see how this works check out Impossible Triangle Illusion Revealed.

Continue reading the full article...


Technical Sketching Optical Illusions

Here are a couple of interesting optical illusions. When I went through college one of the courses I had to take was Technical Sketching. Many of my sketches looked similar to the below drawings but I think all of my drawings could actually be constructed.

mechanical illustration optical illusionmechanical illustration optical illusion
I could be wrong, my professor gave me an "A" but if my drawings were even close to these he may have questioned my sanity and my mother always taught me that when dealing with a crazy person to just smile and back away slowly. :-)

Continue reading the full article...


Curio Shelf Optical Illusion

Sci-Art Bloggers Friday Favorites

Would you allow your family heirlooms to be displayed on this shelf? I like the effect of this optical illusion but I'm not convinced that it would be structurally sound.

If your interested in constructing this shelve check out the update at the end of this post.

Book Shelve optical illusion

This is the Sci-Art bloggers Friday Favorites. The Sci-Art bloggers are a group of bloggers that frequently cover that area where art and science overlap.

Below are some postings from our members that I picked for today's Friday Favorites set.


Artsy Science "Creepy Parasites v.1"
Bibi's Box "Top 40 Magazine Covers"
What Is It? "This Weeks Photos"

I hope you enjoy these posts selected for this week. If you have a site that might meet at the intersection of science and art drop me a line and join the group.

Update: Thanks to Daria you can now build this shelf.

Continue reading the full article...

Finalist, 2005 Weblog Awards

I was lucky to be selected as a finalist for the 2005 Weblog Awards in the category of top 5001-1000 blogs. Please go to the link below and vote for Optical Illusions Etc...

Voting Begins December 5, 2005 and ends December 15, 2005
Click here to vote for Optical Illusions Etc...?

Category: "Best of the Top 501 - 1000 Blogs"

# You may vote once every 24 hours in each poll.
# After voting in an individual poll you will be locked out from voting again in that poll (on the computer you voted from) for 24 hours.

Please vote everyday and thanks for reading Optical Illusions Etc...

Continue reading the full article...


Jesus Optical Illusion

This is an after image optical illusion. When you first look at this image it sort of looks like catwoman in her mask. But alas to see the true image you have to stare at the three dots in the center of the image for 30 seconds then focus on the white space to the right.

Jesus afterimage optical illusion

This optical illusion is my nod toward traditional afterimage illusions. This is only the second (here is the first) that I have put on this site, but I'm sure it won't be the last.

Continue reading the full article...


Stop It! Optical Illusion

The below optical illusion photo was setup and photographed by Claudio Gatti with a Minolta DiMAGE A1 digital camera. I love the illusion of motion created in this image. Well done Claudio!

Stop It optical illusions image

Stop It!
© Copyright 2003-2004, Claudio Gatti
Used w/permission

Claudio Gatti says the following about this image.
I've always been fascinated by this type of perception illusions. My interest started when I studied many years ago perception and colors. I was fascinated by Johannes Itten, The Art of Color , and all his work on subjective color perception. I still have an little booklet in Italian published by Kodak ( which I included in a shot for A touch of Color) which collects several papers on this subject, with many examples of this type of effects. For the same reasons I always loved Victor Vasarely's work .

Continue reading the full article...

Copyright Notice
The documents distributed here have been presented on this blog in the spirit of providing an entertaining venue to educate those interested in optical illusions.

All Flckr.com photos are presented here via Flckr's "blog this" feature. This feature is enabled by each artist on Flckr. If you find material here that belongs to you and you would like to have it removed or credited please contact me and I will gladly follow your wishes.

Copyright and all rights therein are maintained by the authors or by other copyright holders. It is understood that all persons copying this information will adhere to the terms and constraints invoked by each author's copyright. These works may not be reposted without the explicit permission of the copyright holder.