Equidistant colors

[Tobias]

Dear all,

I would like to conduct an attention experiment in which I need to have 9 colors. These should be "equidistant". That is, they should be equally salient on a black background.

The first thing I cam eup with was to use the HSV color space and varied the H value from 0 to 239 with equal distance while keeping the S and V value fixed.

The outcome is quite disappointing. The colors seem to be not comparable at all, some seem brighter, some darker and the subjective distance ('similarity') was rather variable.

Does anyone have a good idea how to choose 9 color that are equidistant?

Thanks a lot,
Tobias

[Nate Vack]

http://boronine.com/husl/

Also it will depend on your monitor calibration, so if you really
care, you'll want to worry about that:

http://www.tomshardware.com/reviews/spyder4-monitor-calibration-image-quality,3581.html

-n

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[David McFarlane]

Tobias,

Googling "equidistant colors" got me to
http://vis4.net/blog/posts/avoid-equidistant-hsv-colors/ . And that
in turn reminded me of the CIE L*a*b* and HCL color spaces, which you
may look up on Wikipedia. I think you can take it from there.

-- David McFarlane

[Tobias]

Nate and David,

thanks for your suggestions. The Cie-Lch and HUSL color spaces seem like a good idea. The only problem is that I need a way to measure "equidistant" colors.
David, this website you linked has some sort of machine that gives you 6 equidistant values. But I need 9, so there seems to be no clear method to get the optimal values without estimating the mouse cursor distance or sth like that.

It would be great if there was some option in a software program.

I guess this is a common problem in psychophysical experiments. I am a bit surprised there is so little about it in google / google scholar.

Best,
Tobias