OP ART creating optical illusions

1. OP ARTcreating optical illusions Optical – belonging or relating to the sense of sight

2. Op Art – 1950’s – 1960’s • What: A mathematically themed style of art that uses repetition of simple shapes, colors, and lines to create illusions such as depth and movement. • Who: M.C. Escher, Bridget Riley, Victor Vasarely

3. How are optical illusions created? An optical illusion (also called a visual illusion) is characterized by visually perceived images that differ from objective reality.

4. The information gathered by the eye is processed in the brain to give a perception that does not tally with a physical measurement of the stimulus source. There are three main types:

5. Literal optical illusions create images that are different from the objects that make them. (Making something look round when it is really flat.) • Physiological illusions are the effects on the eyes and brain of excessive stimulation of a specific type (brightness, tilt, color, movement) Ex. Images where something appears to be moving or changing color when it really is not. • Cognitive illusions where the eye and brain make unconscious inferences. They can also be known as "mind games” (ex. One picture looking like two different ones.)

6. Tips for creating optical illusions • Use opposite (complementary) colors and alternate them • Let size show distance (example, to make an object look far away, make it smaller, to make it look close, make it bigger and overlap!) • Render unrealistic scenarios in a realistic manner • Alter the direction, size, and proximity of lines to create an illusion of movement and depth • Create a design or picture that has duality (appears to be two different things depending on what you perceive to be the positive or negative space.)

7. Bridget Riley’s “Cataract 3” successfully makes the lines look like they are waves on the paper by alternately moving them close together and far apart while also adjusting the thickness of the lines..

9. M.C. Escher used shading to create his illusions. Where he did not shade looks flat while the shaded hands look 3-D, as if they are coming out of the paper.

10. Escher also created illusions by altering perspective within a single drawing. Although each set of stairs are drawn realistically, together they create the illusion of a room that could not really exist.

11. Escher also developed what are known as Tessellations, which are patterns of interlocking shapes or objects.

12. Victor Vasarely used a combination of altering values, colors, shapes and sizes to create his illusions to make things look as if they are popping off of the page.

14. There is no animation or movement within this artwork. The placement of the shapes and colors, along with the varying sizes, create a dizzying effect on the eye that makes your brain perceive movement even though it is not really there.

15. Follow the moving pink dot around the circle and there will be no change in color. Next, focus on the center of the circle and dots will appear to turn green.

16. Look at the entire image – do you see all the black dots? Now try to focus in on one of those dots…..

17. Look at the two sets of circles. Which center circle is larger, the one on the left or the one on the right? • By placing the spheres in different contexts (situations) their sizes appear to change depending on their surroundings.

18. Look at the small rows of squares within design. Which set of pink squares is darker? Which set of green squares is darker?

19. This artwork was made by a middle school student. The illusion was created by using cross- contour lines over forms to give dimension, as well as by manipulating size and overlapping to give the illusion of distance. Shading was also used to enhance the illusion of 3-dimensional form.

20. Cross contour lines are drawn lines which travel, as the name suggests, across the form. Cross contours may be horizontal or vertical, as on the right side of the example, or both. Often, in more complex forms, cross-contours will be drawn at varying angles. In this rather lumpy example, the grid of cross-contours looks a bit like the gridlines on a globe.

21. This artwork was done by an elementary school student utilizing cross-contour lines to give the illusion of a sphere on a flat surface. Where the lines are straight appears flat, where they change and become rounded the image begins to look 3-dimensional.

29. Options for Op Art Project • Create an illusion of depth and movement using techniques (alter line direction, thickness, and placement) similar to Bridget Riley • Use a combination of shading techniques to make a flat drawing appear to morph into a 3-D one, like M.C. Escher • Use color, value, shape, and contour lines to create a 3-D illusion like Victor Vararely • Create a play between positive and negative space to create a dual image. • Create a design of complementary colors and/or black and white to create a dizzying effect. • Create a tessellation (design of perfectly interlocking shapes or pictures), like M.C. Escher. • Create a design that creates an illusion of changing color. (Placing one color on different color/value backgrounds to see how it effects the original color.) This option is the best if you do not have a long time to complete the project! • Create an illusion of your own design using one or a combination of the above techniques.