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How to create equally luminant and saturated colors in online experiments?

Dear community,

I have a rather general question regarding colors and color spaces.: I recently started to work at a new lab where we mainly run online experiments (at least for the moment). We mainly use the bulider (with custom code components) to program these experiments.
We are currently trying to establish a standard procedure to select the colors for our experiments.

To give you an example of what I am exactly looking for: Let’s say I want to present polygons in three different colors in my experiment. All of these colors should be (a) equally luminant (b) equally saturated and (c) equally far apart from each other on the color wheel. So far, my online search has suggested that the CIElab (or the CIELch) space would be the optimal solution to achieve this.

However, since CIElab is a device-independent color space, we have to know the tristimulus coordinates for one or more points that can be used for the conversion (as far as I understood, whiteXYZ is usually used for that purpose).

My question is: Is it possible to get this information for our participants’ monitors in online experiments or is it only possible to get this information when you have physical access to the monitor?

If the latter is the case: Are there any alternatives to CIElab that work for online experiments (for example, I read that HSV might be “good enough” to achive what I want).

Many thanks in advance,

Benedikt