palette or chart of star colors ?

Hi,

To create renderings of stars I need to know their spectral color to
represent them the best I can using a calibrated screen.
For example, I try to render Pollux and its exoplanet.
http://www.astrosurf.org/lombry/alie...renderings.htm (close to mid of
page, left)
This bright star is a K0III, thus orangeous.
But a K5 or K7 star is also "orangeous" but with redder.
So how to know what is the exact tint or palette to use to render exactly a
K0III star (and tens of others) ?
NB. Of course nobody will never tell me that my Pollux is G6 instead of K0
on his creen, but better to render them correctly ;-)

Is there somewhere on the web something that could help me to pick up the
exact color of each spectral class ?
No color palettes includes in office applications uses such a system (but
rather CMY, RGB, etc). So how to proceed ?

I think to a high resolution true color H-R diagram, maybe, but where could
I find such a chart in hires, and online ?

Or isn't there an astronomy application that shows them all correctly (I
think to Starry Night Pro 6 as I'm going to buy it) or even a small freeware
dedicated to stars ?

Do you have another idea to check spectral colors electronically (and if
possible with all intermediate stages, G0, G3, G7...)

Thanks in advance

Thierry
http://www.astrosurf.org/lombry/