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Why does the chromaticity diagram look like that?

(jlongster.com)
276 points samwillis | 2 comments | 26 Jul 24 18:19 UTC | HN request time: 1.636s | source
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PaulHoule ◴[26 Jul 24 20:02 UTC] No.41081764[source]▶
That particular version of the chromaticity diagram makes it look like the colors missing from your display are various shades of laser pointer green as opposed to all the shades of red and blue that are missing because really saturated red and blue primaries are too dim (per unit of energy) to use.

See https://nanosys.com/blog-archive/2012/08/14/color-space-conf...

I learned a lot more about color management than I wanted to know in the progress of making red-cyan stereograms because I found when I asked for sRGB red I was getting something like (180,16,16) on my high gamut monitor which resulted in serious crosstalk between the channels.

Right now I am working with a seamstress friend on custom printed fabrics and I have a flower print where yellow somehow turned to orange in the midst of processing the image and I want to get it debugged and thoroughly proofed before I send out the order... I am still learning more than I want to know about color management.

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1. ahazred8ta ◴[27 Jul 24 18:45 UTC] No.41088485[source]▶
> Right now I am working on custom printed fabrics

You almost certainly need to work in the vendor's CMYK/SWOPv2 color space profile to get the colors to come out right. Ask them. Saturated RGB doesn't convert well. Plan B: desaturate to a slightly grayish yellow.

One example: https://ctnbee.com/en/upload

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2. PaulHoule ◴[28 Jul 24 15:35 UTC] No.41093922[source]▶
The vendor specifies sRGB so sRGB it is. For that matter my Epson printer specifies a native color space which is basically RGB, I wish I could tell it to lay down various amounts of C, Y, M and K pigments I can't.

I have the real object to compare with the screen and with paper and fabric prints under various viewing conditions. I am going to print small samples, order a set of RGB labeled color swatches, etc. I have to tighten up my whole chain because I have a wide gamut monitor and also produce Display P3 for social sharing and would like to prototype realistically on my inkjet.