To me at least, the gray shades look almost exactly alike. Why were 11.1% and 20% chosen as the intensities for the gray shades?

I think that Hugo said that those shades were chosen because they were the least "flickery" shades on the VFD display.

As I understand it, it's possible to program your own shades if you're writing your own software for the unit. So if, for example, you wanted to code up your own movie-player applet, you could do it and be in control of the palette yourself. Then you could make your own choices as to what was "too flickery" or not.

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Tony Fabris