1. © Van Lier & Vergeer, 2006 Visual Illusion Contest 2006 Rob van Lier & Mark Vergeer NICI, Radboud University Nijmegen, The Netherlands Catching Patches

2. © Van Lier & Vergeer, 2006 A fuzzy grid...

3. © Van Lier & Vergeer, 2006 A fuzzy grid. Dark background  no patches

4. © Van Lier & Vergeer, 2006 With luminance edges however...

5. © Van Lier & Vergeer, 2006 A fuzzy grid. Dark background, light edges  dark patches

6. © Van Lier & Vergeer, 2006 A fuzzy grid. Dark background, dark edges  dark patches (weak )

7. © Van Lier & Vergeer, 2006 A fuzzy grid. Light background  no patches

8. © Van Lier & Vergeer, 2006 A fuzzy grid. Light background, dark edges  light patches

9. © Van Lier & Vergeer, 2006 A fuzzy grid. Light background, light edges  light patches (weak)

10. © Van Lier & Vergeer, 2006 Another grid, but now with thicker fuzzy bars...

11. © Van Lier & Vergeer, 2006 A fuzzy grid. Dark background  no patches

12. © Van Lier & Vergeer, 2006 A fuzzy grid. Dark background, light edges  dark patches

13. © Van Lier & Vergeer, 2006 A fuzzy grid. Dark background, dark edges  dark patches (weak )

14. © Van Lier & Vergeer, 2006 A fuzzy grid. Light background  no patches

15. © Van Lier & Vergeer, 2006 A fuzzy grid. Light background, dark edges  light patches

16. © Van Lier & Vergeer, 2006 A fuzzy grid. Light background, light edges  light patches (weak)

17. © Van Lier & Vergeer, 2006 Patches follow random changes of the edges at the crossings...

18. © Van Lier & Vergeer, 2006 Random edges at intersections – 1

19. © Van Lier & Vergeer, 2006 Random edges at intersections – 2

20. © Van Lier & Vergeer, 2006..and using a ‘Geier pattern‘...

21. © Van Lier & Vergeer, 2006 A Geier-modified Hermann grid – no patches

22. © Van Lier & Vergeer, 2006 The return of the patches...

23. © Van Lier & Vergeer, 2006..catched between the edges!

24. © Van Lier & Vergeer, 2006 The end Thanks!