Choose two inks, then read their contrast in a real paragraph.
Perception & Contrast Crucible
Explore modern APCA (Advanced Perceptual Contrast Algorithm) vs legacy WCAG 2.1 math, ocular halation dispersion on OLED screens, and human photoreceptor cone deficiencies.
Read the pair in context.
Read the details before saving this specimen.
8.48:1 luminance contrast · meets the 4.5:1 normal-text contrast threshold. This alone does not establish page accessibility.
Vision filters are approximations, not representations of every person’s vision. APCA is a research model; its score is not WCAG 3 conformance.
Keep one. Try another.
Pin a plate before changing the controls. Each pin keeps its own recipe and lighting context.
Carry this specimen into another tool
The image travels locally in this tab with its source recipe. This is a flattened plate: the destination does not recreate fluid motion or convert material coefficients.
Models human non-linear spatial vision across light/dark backgrounds.
Mathematical relative luminance ratio ignoring font weight and halation.
Perceptual lightness invariance guarantees that interface typography maintains predictable cognitive legibility across light, dark, and diurnal shifts without destroying photoreceptor acuity.
SIMULTANEOUS COLOR DEFICIENCY MATRIX
Observe how your active foreground/background formulation appears across all human vision phenotypes simultaneously.
Archival Inquiry & Search Tree
Interactive recursive knowledge graph answering high-intent questions on OKLCH color science, diurnal UX, diegetic materiality, and machine governance.