Re: Apple IIgs Color Dither Problem

["Michael J. Mahon" <mjmahon@aol.com>]

Immortal Nephi wrote:
> Please explain why CRT / LCD screen for VGA monitor show colored
> vertical strip which is called dithering, but real Apple IIgs' monitor
> does not show dithering.
>
> Do you have a way to combine dithering into solid true color on any
> Apple IIgs emulator?  I know that 640x200 resolution has only four
> colors each horizontal line.  You may need color dither translation
> table.

As Eric pointed out, the resolution of a modern monitor is much better
than the Applecolor RGB, so the dithering--which is supposed to be
averaged out to be useful--is resolved into fine lines of blue and
white.

If you are not seeing 640 fine lines, but a considerably smaller
number, then you are seeing a moire pattern formed by the "beat"
between the 640-pixel dithered line and the LCD's real pixels and/or
its resampling clock.

-michael

NadaNet and AppleCrate II: parallel computing for Apple II computers!
Home page: http://home.comcast.net/~mjmahon

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