I'm currently getting great results with the compressed HSVA colour system workflow using coolors.co:
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- Use smartphone flash as a white light source to shine through the filament
- My reference is:
- 50% - Max transparency whilst still retaining 100% saturation
- 100% - Effectively opaque for 1.75mm filament
- My reference is:
- Get an offcut of filament (or 3d print)
- Place it next to a white reference
- I'm using my white spacebar
- Max out saturation and brightness sliders
- Shine flash on filament sample
- Move hue to nearest 5 degrees
- Move brightness to nearest 10 percent
- Move saturation to nearest 10 percent
- I find this to be the least confidence-imbuing slider since colours look more similar, particularly at medium-low brightness values
With this, I can get a confident compressed-HSVA mentioned in this log, but I still move the sliders around by 1 step to make sure I've got the right colour:
Confident YES:
![]() | Confident NO:![]() | Confident NO:![]() |
There was no shine-through for the mint, thus the colour for this not-quite-cyan is 35.a9a.
Surprisingly, my pink is so much further away from the ideal magenta. The hue of the mint is only out by 5 degrees, yet the pink is out 25 degrees and admittedly desaturated:
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It also has a bit of a glow when the filament is lit from behind, so its value could be 70.6a9.
One possibility for the hue is screen colour reproduction, and I know that pinks have always been questionable on various IPS panels. On my OLED phone, this same colours looks much more vibrant... oversaturated even. On my 9th gen iPad I happen to have, the hue is 315 and other values are unchanged. This is part of the reason for the compressed colour space; there are so many variables that the precise value isn't that meaningful.
Considering a substantial amount of people have an unmodified iPad, touted with "TrueTone" technology, I will use it as the hue reference.
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