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macrumors regular
Original poster
Feb 9, 2004

TLDR; How can I create a LUT for Photoshop of just 22 colors? Or something similar in Affinity Photo?


I'm creating a portret, using 20 x 28 = 560 plastic bottle caps for 'pixels'. Because I knew that subtle colours would be hard to find, I made a photo with bright blue, red and green lighting and enhanced it even more, so the pixels would be easier to match with the bright colours of the bottle caps. I reduced the resolution to 20 x 28 pixels (image on the left).

I spend quite some time, searching for coloured bottle caps.. 😑

In Photoshop, I created a matching colour table (.act file) with the menu Image > Mode > Indexed Color of 22 bottle cap colors, and used it on the image (on the right).

Although it's not bad, I want to experiment a bit more with the colours of the image, to find the optimal 'form' or 'translation' to coloured caps.

In order to do this, I now have to guess / do a blind adjustment, then make an indexed image of it, go back and repeat.

It would be a lot easier if I could immediately 'live' see what I am doing, via a LUT adjustment layer in Photoshop, but how can I make one? Is it even possible to use a LUT file this way into just 22 colours? Of course, I'm open for suggestions in other tools, like Affinity Photo.

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