I'll Show You How to Paint This Optical Illusion

James Gurney shows how to paint an optical illusion in acrylic. The cylinder is covered with a checkerboard of light and dark squares arranged so that the dark square in light is the same paint mixture as the light square in shadow. The diagram demonstrates how our visual system uses context cues to override the raw information coming from our eyes. Sample from the new video tutorial "Gradients: Color, Form, Illusion." Download or stream at Gumroad: https://gurneyjourney.gumroad.com/l/ElCti/ Also available as a DVD: https://jamesgurney.com/products/gradients-color-form-illusion International DVD sales: http://Kunaki.com/MSales.asp?PublisherId=136361 STEP-BY-STEP METHOD ● Draw it first with pencil on watercolor paper or illustration board. ● Paint the gradients for the light tones first. ● While painting the cylinder, paint the background tones and cast shadow, too. ● When those passages are dry, paint the darker squares. ● The cylinder appears to be lit from the left with warm light and cool shadows. ● The light yellow squares become darker and cooler as they transition to the shadow side, becoming that neutral gray. ● Mix plenty of that gray because you'll need it for the other squares.. ● The dark squares in that shadow side get warmer and lighter as they transition to the light side. ● I used Tri-Arts liquid acrylic: Cobalt blue, Ultramarine blue, Cadmium yellow medium, Raw sienna, Red oxide, Quinacridone red, Ivory black, Titanium white, Neutral gray (about equal to Pantone 424C Pantone color swatch book: https://amzn.to/3hqz2QH ) MATERIALS You can use other brands of acrylic, gouache, casein, or oil, as long as it's opaque. Liquitex acrylic basics neutral gray: https://amzn.to/3twZ6hW Golden fluid acrylic set: https://amzn.to/3yZQYHR Acrylic gesso: https://amzn.to/3jZIkVt Richeson casein paint set: https://amzn.to/2L02U6R Pentalic watercolor sketchbook: https://amzn.to/2L989y2 Water cup: https://amzn.to/2soTw2L Rigger brush (for fine lines): https://amzn.to/2YPm9JA Richeson travel brush set: https://amzn.to/2xwq1Rr Richeson “Grey Matters” brush set: https://amzn.to/2YeNO0P • M. Graham gouache primary set: https://amzn.to/2Zwd6rt • Winsor & Newton gouache primary set: https://amzn.to/2JiDMbo • Holbein gouache set: https://amzn.to/2KW4s1j • Royal Talens gouache set (8 colors): https://amzn.to/2MGftGf • Shinhan Pass watercolor/gouache hybrid set: https://amzn.to/2xw7EvV OTHER VIDEO TUTORIALS: “How to Make a Sketch Easel” (DVD): http://kunaki.com/Sales.asp?PID=PX00Z4M3X BOOKS BY JAMES GURNEY: Color and Light: A Guide for Realist Painters: https://amzn.to/2JhWtfc Imaginative Realism: How to Paint What Doesn’t Exist: https://amzn.to/2LbVHhc Dinotopia: A Land Apart from Time: https://amzn.to/2xyamRM OTHER OFFICIAL SITES Instagram: https://www.instagram.com/jamesgurneyart/ Pinterest: https://www.pinterest.com/GurneyJourney/ GurneyJourney Blog: http://gurneyjourney.blogspot.com/ JamesGurney Website: http://jamesgurney.com/ Facebook group "Sketch Easel Builders": https://www.facebook.com/groups/403006076777641/?source_id=121255121263267 Facebook group "Color in Practice": https://www.facebook.com/groups/160510955315435/ Some links are Amazon affiliate links. I receive a small royalty at no cost to you.