For Coloral VB light/dark references, the app minimises CIEDE2000 along the measured Lab* segment. Coloral TC dyes and electrolytic colours use their single measured plaques. L*, a* and b* all contribute.

The optional fourth catalogue, “Coloral TC · estimated light/dark”, explores only a short segment around each organic dye measurement: up to 3 Euclidean CIELAB units per side (6 total), along the direction from the approximate undyed substrate Lab* (86, −1.10, 0.80) to that measurement. This is a geometric hypothesis, not a measured trajectory, an accuracy interval or a dose prediction. It does not connect the whole path to the substrate. Points at or above substrate L* stay single points.

The fourth catalogue works independently. If both Coloral TC dye catalogues are selected, each dye appears once with its best simulated result and its original measured-point ΔE00. Original points stay visible in both charts. Deselect estimated light/dark to return to measured-point matching. Inorganic and electrolytic colours are never simulated. The Excel and catalogue measurements are not changed.

Coloral TC dyes (including one inorganic gold reference) and Coloral TC electrolytic colours can be selected independently of Coloral VB. The nine electrolytic references remain separate measured points, not connected curves. A poorer single-point match does not establish that a dye could not match at another concentration.

Supplier guide concentrations and pH are not recorded conditions of the measured plaques. Coloral TC results therefore show no estimated dose and do not enter the blend search. Electrolytic colours are colour comparisons, not interchangeable dye recipes.

The “very close”, “close” and “verify” ratings are initial working thresholds. They should be refined after comparison with visual and production acceptance.

Single-dye search samples each eligible measured or short simulated segment and refines the local minima of CIEDE2000 (kL = kC = kH = 1), including both endpoints and the original measured point. VB dashed extensions never contribute to the search. ΔL*, Δa* and Δb* always mean the proposed colour minus the target.

The experimental blend search screens every pair and triple with concentration data, then refines the strongest candidates using continuous proportions and segment positions. It no longer fixes each dye at the target L* or uses 5% steps. Contributions sum to one, with a 2% numerical floor per dye. This is a heuristic Lab-space search, not a certified global optimum or a physical formulation model. A third dye is shown only when its model ΔE00 improves by at least 0.05.

For each contribution, c(t) = c(light) + t × [c(dark) − c(light)]; its starting dose is model weight × c(t). Different combinations can predict similar Lab* but different doses. More concentration measurements and real mixture trials are needed for a calibrated formulation model.

Conservative proposals hold the selected Top-5 comparison point as the base reference. The base retains at least 90% of the Lab-space contribution; all correcting dyes together contribute at most 10% of the base's calculated g/L. These are practical search constraints, not a chemical validation. Select a particular Top-5 dye to prefer grey, brown or another base. Only improvements over the best single dye are shown.

Both built-in catalogues were measured with a Konica Minolta CM-700d at D65 / 10°. SCI/SCE and aperture are not recorded. Use compatible measurement and process conditions. Swatches use an approximate D65 / 2° display conversion, not an exact conversion between observers, and may be gamut-clipped. This does not alter measured Lab* or ΔE00 ranking. Reports are rendered locally at 200 dpi with SurTec attribution.