But as advertisers always like to take the work of famous artists and repurpose it to promote their own products, it is not entirely surprising that this technique has since been incorporated into billboards. Of course, that’s not to say these ads aren’t artistic in themselves. After all, it takes a lot of thought and energy to design something that will be displayed outside, but only be visible at certain times of the day.

As a matter of fact, this particular New Castle billboard was created by another set of artists, Ellis Gallagher and Pablo Power. It is made up of more than 3000 bottle caps and can only be seen at night when the external light shows on it at exactly the right angle.

Believe it or not, this billboard is in my town and I still haven’t even had a chance to see it. I think it’s time I head out that way to enjoy the illusion in person.

Youtuber who goes under the name of brusspup noticed how this illusion has been around for a long time but always in the form of an image. His goal was to take it away from a flat piece of paper and turn it into a real, life-sized illusion that people could interact with. Obviously, brusspup has succeeded. He even included a scaled-down template for us to download and play with (file courtesy – brusspup).

Here’s how the author explained the effect and what he has done to achieve it:

The illusion works because of the “shadow” that falls on the checkerboard. Lets think of the square that the shadow falls on. Now picture that the shadow doesn’t exist: you would see a light colored square surrounded by the dark colored squares. But when the shadow falls on top of that light colored square, the shadow causes the shade to become darker but it also causes the surrounding darker squares to become darker. So within the shadow region the brightness and darkness of the squares are still relative to one another. But they are no longer relative to the squares that lie outside of the shadow.

So if you were able to pick up the middle square and move it to one of the outside dark squares, they would be 2 different shades, But the trick is ..that when you move the square you are moving it WITH the shadow still printed on the square. So now you’ve moved it out of its relative area, outside of the shadow region (but with the shadow still printed on the square) ..to the area where it’s the same shade as the “dark” square.

I understand how my English can sometimes sound crippled, specially in situations that require in-depth explaining. So I apologize once again, but also thank you for all of the warm feedback regarding my diploma!

Btw, to show you how important all of your suggestions and bug reports are, I’ve fixed the mobile theme’s width (be sure to check this site on your smartphones and report your experience). I’ve also included the “Next Random Illusion” button at the footer of each article in our mobile version :) …oh, and for today’s post – I just hope it doesn’t need any additional explanation (hint).

Concerning the illusion, it was created by an artist called Chow Hon Lan. It depicts somewhat puzzling situation these two workers found themselves in. It is for you to decide if there are really two guys present, or is it merely an illusion?

I apologize for that, mostly because of my manners, but also lack of skills and additional staff… So here it is: Merry Christmas and Happy New Year!!

Now let’s return to our topic. To see the genius of Belgian artist Fred Eerdekens, the lighting is very important. That’s because Eerdekens’ work relies on the shadows cast by sculptures — which are made of bent wires in this example — to unveil the hidden message to the viewer. Can you read all of the Eerdekens messages? What do they say?

Update 2: Unfortunately, original author asked us if we can remove his photo of the site, which we are obligated to do, so instead I’ve added this magnificent installation by Fred Eerdekens.

Lydia Roe found this peculiar photo of some band I never had the opportunity to learn of. The illusion is more fun orientated than being puzzling. Still, it turned out fine. What you see here is a singer and guitarist Laura Marling casting an unlikely shadow. Any clue how this happened? More similar fine illusions can be found via #shadow tag!

On the other hand, I have received this magnificent installation, one that greatly resembles Tim Nobel and Sue Webster’s optical illusion opus. Check the garbage formation. It doesn’t resemble to anything meaningful. But cast a light on it from certain point of projection, and the marvelous sailing ship magically appears.

Many shadow illusions can be seen if you follow the #shadow tag, but what’s more staggering (for me) is how you didn’t like the Trashy @ Sign Shadow. Perhaps because it was put aside to our new iPad App?

Duncan posted a comment in one of our previous posts, where he shared an interesting picture. Depending on your monitor luminance, you should have no problem reading the (partial) letters below. The message is straight and clear. However, look what happens if we adjust the output levels. How come it was easier reading the text when only half of the letters were shown? Think it has something to do with this study?

And now the illusion… I always mix the two paragraphs; one describing the illusion, and other talking about site news. I think the former one should come in second. Anyway, do you know how the photographer made them screws levitate? It took me a second or two, but then I remembered we had something very similar posted month ago. Btw here’s the Fan Group signup, again. You’re just few clicks from becoming Our Fan: