You're right. Try bringing the "Checker Shadow Illusion" as a .jpg into Photoshop or GIMP and check the color values. Surprisingly in both A and B locales they'

You're right. Try bringing the "Checker Shadow Illusion" as a .jpg into Photoshop or GIMP and check the color values. Surprisingly in both A and B locales they're 120,120,120 (RGB). More curious is experimentation with the eraser. Using the 120s, seemingly similar black squares can be grayed-out[?].