[Coco] The myth of the Coco3 256 color mode :)

[Robert Gault]

Joel Ewy wrote:

> This has been discussed extensively elsewhere, if not on this list.
>
> 1 byte is used to represent a pixel.  There are 256 different patterns possible
> using 1 byte.  It is possible that some of the artifact colors that result from
> this are indistinguishable from others.  But the total possible number of colors
> is 256.  But a real palette of 256 actual colors was selected by several guys a
> few years back (I credited Jason Law, Briza, Robert Gault and Potatohead at the
> end of the slideshow for those with the fortitude to watch it all the way
> through) and the photos were mapped to this palette in GIMP.
>

Joel,

You've exactly described the issue for which discussion with attached images and 
programs will be easier to pursue at
http://www.tandycoco.com/forum/viewforum.php?f=23&sid=3014c6a337f84d675ee33e05067f3c5e

Since it takes more than one Coco3 pixel to generate the full range of artifact 
colors, there is not a one to one correlation of .bmp pixels to Coco pixels. You 
need at least a 2x2 block per .bmp pixel to come close to the right colors. 
Better colors would be 4x4 but that would not give good screen resolution.
Further if anyone ran the demo program posted earlier, you will see even on an 
RGB monitor with the wrong colors that there is a physical shift in the 
horizontal direction required to get the right artifact color. This shift will 
disturb image resolution.

Robert