[scribus] [OT] How many different colors?

[John Culleton]

On Thursday 09 December 2010 08:17:42 Gerard Cunningham wrote:
> On Thu, 2010-12-09 at 12:56 +0100, Juraj Fedel wrote:
> > On Wed, Dec 08, 2010 at 09:18:01AM -0500, Gregory Pittman wrote:
> > > I think perhaps a more important consideration is the ability
> > > of the eye/brain to differentiate colors in a useful way.
> >
> > This is exactly what I am looking for! And I am aware of most
> > problem you mentioned. It is my fault that I can not ask qestion
> > simply.
> >
> > I am looking for a list of colors that are distinct enough for
> > most people not to be confused when comparing them.
>
> Part of the problem is that there are no agreed names for colours.
> Colour perception is subjective. The link below isn't exactly
> scientific, but it does give a flavour of some of the problems:
> http://blog.xkcd.com/2010/05/03/color-survey-results/

Color blindness, full or partial, seems to be a masculine trait. Few 
or none of the female gender suffer this problems but about 10% of 
males have a problem. 

Do you want colors that can be distinguished side by side or colors 
that can be recognized by name when standing alone? 

For CMYK colors easily distinguishable from another I suggest the 
Galaxy Gauge Color Map Pro tool, and the color harmonizer wheel 
display part of that tool. Around the outer rim it shows 24 colors 
with their cmyk formulas. Then each such color is split into columns 
of darker and lighter shades.   If you use every other color around 
the outer rim you should have 12 easily distinguishable colors. Or you 
could pick one and skip two yielding 8 colors.  If you skip three you 
get 6. The six most easily distinguished colors for me are:
0,100,100,0
0,0,100,0
100,0,100,0
100,0,0,0
100,100,0,0
0,100,0,0
These are indicated on the inner part of the wheel with solid lines. 

If you play with the K factor then the number of easily 
distinguishable colors multiplies by 4, using k factors of 0, 25, 50, 
and 75.  That yields 18 more colors for a total of 24.  If you hold k 
as 0 and add in the paler shades by successively diminishing the CMY 
colors listed above by 25% you get 18 more easily distinguishable 
shades for a total of 42 colors.  An example of one color and its six 
variants:
100,0,100,0 (as listed above)
Darker shades
100,0,100,25
100,0,100,50
100,0,100,75
Paler shades
75,0,75,0
50,0,50,0
25,0,25,0

All in all the question you pose can be satisfied to your own 
satisfaction at least by using the Galaxy Gauge  color wheel mentioned 
before. Nothing works better than a live example with the CMYK factors 
listed for each segment. The above mentioned tool provides that 
information.

-- 
John Culleton, 
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