[Coco] Coco3 CMP color swatches

[Robert Gault]

There are two issues here, 1) what are the color names and 2) what are 
the equivalent 24 bit value. There is no need to measure anything to get 
24 bit values. Just assume the Coco DAC is full on at 3 and full off at 
0. Scale that proportionally over the 24 bit values of 0-255. The 
problem is that all monitors have slightly different color tuning even 
with the best intentions that will make all Coco images look slightly 
different. It is possible that the Coco DAC is of low tolerance and that 
will cause even larger differences in color. Even the amount and type of 
room lighting will have an effect on perceived color. Tandy did not fill 
in the table of color names for a reason. Tandy could have printed 
un-named color swatches, but the expense of doing that in a useful 
fashion would have been too high.

Names are another matter entirely and I don't believe there is any 
suitable method of getting these short of using standardized color 
charts and their technical rather than descriptive names. Any method of 
printing the color swatches will not result in permanent color so naming 
the swatches would be an exercise in futility. Most people will barely 
be able to distinguish nearest neighbors in the 64 palette color 
selection unless they are side by side and certainly can't when the 
level of color is increased.

My suggestion is that the best names for the Coco colors are their RGB 
values, ex. 2R3G1B and let it go at that.

Kevin Diggs wrote:
> Hi,
> 
> Robert Sherwood wrote:
> 
>>
>> Of course, you also have to consider the effects of converting the 
>> image to GIF or JPEG as well.  The only way I know to be certain of 
>> having perfect colour reproduction in a digitized image is to provide 
>> it in a 24-bit uncompressed format (such as BMP or TIFF.  PNG might 
>> work - I'm not as familiar with that.)
>>
>> All that being said, I think it's certainly worthwhile to go ahead 
>> with the experiment and see how the results compare to the previous 
>> MESS screenshot.  It's probably also worth it to try the same with the 
>> digital and film cameras as stated sometime earlier.  Although with 
>> film, the printing process introduces way too many output variables to 
>> be very accurate for producing swatch-like samples.  Either slides, or 
>> a scan from negatives would be the best option here.
>>
>> --Rob
>>
>>> Allen Huffman wrote:
>>>
>>>>
>>>> What happens if you just grab a frame using a TV digitizer? (With
>>>> composite inputs.)
>>>>
>>>>         -- Allen
> 
> 
>     What about hooking a scope up to the RGB lines and seeing what the 
> DACs actually put out for the 4 values and using that to guide the 
> conversion from 2 bit to 6 or 8?
> 
>                     kevin
>