Chromilla Pro tool
Two tubes with the same pigment code do not always mix the same. Each maker grinds the pigment differently, uses different binders and fillers, and student lines often carry less pigment. Even the same tube can vary a little from batch to batch. That is why a recipe can be right on paper and still come out slightly off on your palette.
Tube Calibration lets you measure your own paint. You paint two small swatches of a tube, scan them with your phone, and from then on Chromilla uses your measurements for that tube instead of catalog averages.
It matters most for strong, staining paints such as phthalos and quinacridones, where a small difference in strength changes a mix a lot, and for whites, which vary more than most painters expect.
This tool is part of Chromilla Pro. You can read how it works below; using it needs Pro.
Step 1
Paint two swatches
A patch of the paint straight from the tube and a patch mixed with white, on white paper.
Step 2
Scan them
Photograph both in even light. Chromilla reads the color and corrects for the paper.
Step 3
Mix as usual
Recipes that use that tube now follow your calibration and are marked calibrated by you.
Your student-grade phthalo blue is weaker than the catalog value, so every green recipe comes out too yellow. You calibrate that one tube with a masstone and a tint swatch.
Chromilla now knows your blue has less tinting strength, so the next green recipe calls for a little more blue than before. Only that tube changes; every other paint keeps its catalog values until you calibrate it too.