• Do these squares have the same brightness?

  • Mach bands
    Do you feel the right side of each band is darker than the left side?

  • Hermann grid
    What do you see at the intersections?

  • Scintillating grid
    What do you see at the intersections?

  • Fraser illusion
    Are the grids crooked?

  • Munsterberg illusion
    Are the horizontal lines in parallel with each other?

  • After image
    First fixate on the cross on the left for a minute, then quickly move to fixate on the cross on the right. What do you see?

  • Do you feel the rings are rotating?