“Illusion d’Optique” Magic Playing Cards

For Art, Math and Magic Lovers!

Order now your exclusive “Illusion d’Optique” playing card deck designed by illusion Master Gianni A. Sarcone!

Packaging printed with optical ink and placed in a protective transparent plastic case.

54 eye-popping optical illusions to play and to experiment with!

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PERCEPTION OF BRIGHTNESS

In the example below, in the left column, you can see two apples—one green, one red—appearing as a single solid color with a black cross over them. Now, if we remove the thick black lines, each apple clearly appears divided into four quarters of different shades—even though they are exactly the same in both columns, with and without the black cross.

Here’s a trickier version: with the black grid in place, the large green square appears uniform. Take the grid away, and it turns into a full-on checkerboard…

shade contrast 2

This occurs because in our visual system there is a mechanism that enhances the contrast of the outline of an object relative to its background: it is called ‘lateral inhibition’. Thus, even small differences in brightness between adjacent zones or objects are deliberately increased by the brain to better distinguish them. So, when the brightness boundaries of the color zones are concealed, the cues the brain needs to trigger the lateral inhibition mechanism no longer exist and consequently we become “blind” to variations in color brightness. The illustrations above have been taken from my book “Drawing Optical Illusions” who was translated in many languages. The book is still available from Amazon.

Drawing optical illusions

This eye-catching, colorful book is designed to inspire those artists interested in optical illusions and as an invaluable reference tool for people who to wish to create them. In clear, easy steps, this book shows people how to design a range of original and classic optical illusions and even how to create their own personalized illusions.

Mondrian Meets… (My Tribute To Mondrian)

Here are two projects involving the geometrical-constructive art of Piet Mondrian, one of my preferred artists, the golden ratio and ϕ. For this purpose, I used the same color palette favored by Mondrian: yellow, red, blue, black and gray.

Mondrian meets Pythagoras and Fibonacci

In the first project, I used squares, that are proportional to each other by the golden ratio or ϕ, to prove the Pythagorean theorem as shown in the Zhoubi Suanjing (or Chou Pei Suan Ching – 周髀算經), one of the oldest Chinese mathematical texts (circa b.c. 200).

Zhoubi Suanking theorem Continue Reading

KINECHROMATICS: A new three-framed animation

Kinechromatics (patent pending) is a method of my invention for animating static images through retinal persistence and controlled interactions between additive and subtractive color systems. It produces apparent motion by sequential color filtering across layered chromatic structures, rather than relying on conventional frame-by-frame animation.

Kinechromatics static image

The static image above is made of 3 layers having each a different subtractive primary color (magenta, yellow, or cyan) blended in ‘multiply mode’…

What happens if we alternately overlay this image with transparent colored acetate sheets, each carrying an additive primary color (red, green, and blue)?

Kinechromatics red

Kinechromatics: red filter
When viewed through a red acetate sheet, the magenta and yellow components are largely absorbed, while the cyan layer remains visible, appearing black.

Kinechromatics green

Kinechromatics: green filter
Through a green acetate sheet, the cyan and yellow components are suppressed, revealing the magenta layer in black.

Kinechromatics blue

Kinechromatics: blue filter
Through a blue acetate sheet, the magenta and cyan components are reduced, allowing the yellow layer to emerge but appear black due to its lack of transmission in the blue range.

The animated GIF below produces a continuous motion effect using only four elements: a static base image and three full-color layers blended in multiply mode.

Kinechromatics animation

Colored light can also replace acetate filters, creating a seamless optical animation. Stroboscopic illumination in primary colors has the added effect of merging perceptually into white light, making the transitions visually smooth. This approach can be particularly effective in museum or gallery installations, offering a direct demonstration of how color interaction is processed by human vision. The setup consists of a static image containing the Kinechromatics pattern, illuminated sequentially by red, green, and blue projection, as shown in the animation below.

For inquiries about exhibition or collaboration, feel free to contact me.

projector

A second example, a simple animated dancing skeleton, demonstrates the same principle:

dancing skeleton

 

See also:

Kinegrams

Bidimensional Müller-Lyer Illusion

I am working on a new two-dimensional variant of the Müller-Lyer illusion… You may be surprised to know that the Müller-Lyer illusion isn’t only linear: it involves plane geometry too! In fig. A shown below, the ends of the blue and red collinear segments, arranged in a radial fashion around a central point, delimit two perfectly concentric circles. However, for most observers, they seem instead to define a large ovoid that circumscribes another one, slightly eccentric (Fig. B). This comes from the fact that the red segments seem to stretch towards the lower part of the figure, while the blue segments seem to stretch towards the upper part of the same. As you can see, in this variant comes also into play the “neon color spreading” effect. In fact, a bluish inner oval-like shape appears within the black arrow heads (Fig. A), though the background is uniformly white.
Müller-lyer oval

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Illusive Op Art Skulls

I am currently working on new “neon color spreading” effects. Have a look at the pictures below… Though you perceive fluorescent grinning skulls, the vertical white stripes don’t contain any color at all, they are uniformly white! The trick lies on the fact that some black lines have very thin color edges. This illusory shading effect is also known as “subjective transparency” or “Tron effect”.

The neon color effect was first observed by D. Varin in 1971. The human ability to perceive a neon effect may be a remnant of the development of our power of sight under water at extreme depths, where light is very poor.

My Op Art Skulls are available as prints and t-shirts from my online store.

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Emerson’s Secret

When Crayola‘s senior designer Emerson Moser retired in 1990—after 37 glorious years of loyal service—he finally confessed to a little secret: he was color vision deficient! Moser went on to produce a record 1.4 billion crayons during his career…
While any type of color vision deficiency (color blindness) could make crayon production difficult, complete color vision deficiency, where someone can only see in shades of gray, is extremely rare. About 99% of color vision deficiency involves just the inability to distinguish between some pairs of complementary colors.
So, if you’re wondering about your own color vision, feel free to take the test on my website.

crayola crayons

What color does it look to you?

1 in 12 people have some sort of color blindness that makes them unable to distinguish certain colors or shades of colors from others. Color blindness is, however, an inaccurate term to describe a lack of perceptual sensitivity to certain colors; a more precise term is: Color Vision Deficiency (CVD). Color blindness is the most commonly used term though it is misleading if taken literally, because colorblind people CAN see colors, albeit they cannot make out the difference between some couples of complementary colors. Color vision deficiency is not related to visual acuity at all and is most commonly due to an inherited condition. Red/Green color vision deficiency is by far the most common form, about 99%, and causes problems in distinguishing reds and greens. There is no treatment for color vision deficiency, nor is it usually the cause of any significant disability.

The most commonly used test to detect color vision deficiencies is the Ishihara Color Test.

Color vision deficient people have a tendency to better night vision and, in some situations, they can perceive variations in luminosity that color-sighted people could not. In fact, most color blind people can easily read what is written in the dotted pattern below… If you fail the test, that means you probably have the full range of color sensitivity that is attributed to color-sighted people.
[Highlight the blank space to see the answer: NO]

Reverse Ishihara Color Test

Different but Equal

It happens sometimes to read on a snack the following notice: “with chocolate taste”, written in uppercase. This statement tricks our mind! In fact, the vast majority of us think that such a snack MUST contain chocolate, no one thought however that a flavor is not a substance and most probably the snack we bit into contains only an ‘illusion’ of chocolate.

The same occurs with colors, our brain is easily tricked by them. Colors are just like ‘flavors’, they may smell, pardon… look like a specific color, but they are just an illusory subjective sensation, not an ‘external’ reality. Colors undoubtedly change depending on their surrounding or the context in which they are viewed. More mind-blowing still is the fact that colors that are identical may appear to be different under certain conditions, and colors that are different may look the same. Such a curious effect is called “color induction”. Continue Reading