Three points along the gray axis
Pick a reference standard — its certified Lab values fill the reference rows. Measure those same three targets with your NR200 and enter the readings into the measured rows. The correction is a per-channel linear fit (slope + offset) on L, a, b independently. Not ISO-certified; a defensible neutral-axis correction. For full instrument characterization, use Tier 2.
White
Mid-Gray
Black
24 patches · 3×3 matrix in XYZ
Measure all 24 patches of an X-Rite ColorChecker Classic with your NR200. The tool fits a 3×3 correction matrix in XYZ space using least-squares regression — the same approach professional ICC profile builders use. References are the certified post-November-2014 ColorChecker Classic targets (D65 / 2°). You don't need all 24: the fit works with 8+ patches; accuracy improves with more.
Lab → HEX in batch
Paste many Lab measurements at once. Each row converts using the selected
calibration tier and three hex renderings: Lab native (CSS lab()),
MINDE (minimum-ΔE gamut map to sRGB), and Vivid (oklch
chroma + lightness boost). Format: name, L, a, b or
L, a, b · one per line · lines starting with # are comments.
Measure a single sample
Enter the raw NR200 reading for a filament sample. Choose which calibration tier to apply — corrected Lab and three rendering variants update live.