Blackbody (Plotly)

Summary

Blackbody (Plotly) is a sequential colormap from plotly. Lightness spans 0.00–1.00, hue sweeps 256° from red to blue, and order holds under all three colorblind simulations.

Plotly 5-anchor blackbody radiation (with cool tail); distinct from moreland.black-body.

Perceptual profile (OKLCh)

• Lightness: 0.000 → 0.824 (range 0.999, min 0.000, max 0.999); non-monotonic; midpoint 0.850
• Chroma: min 0.000, max 0.238, mean 0.122
• Hue: 0.0° → 256.4° (span 256.4°), path monotonic-cw; quadrants: red, orange, yellow, chartreuse, blue
• Endpoint temperature: null → cool
• Perceptual ΔE: total 178.7, mean/step 0.701, max step 1.935, smoothness 0.430, speed 0.701

Colorblind safety (ΔE under simulated CVD)

• Protanopia: ΔE total 137.1; preserves order: yes
• Deuteranopia: ΔE total 139.2; preserves order: yes
• Tritanopia: ΔE total 157.0; preserves order: yes

Related

• Family: plotly
• Source: plotly.js / plotly.py contributors
• Similar sequential maps: Earth (Plotly), Electric, Jet, Plotly3, Portland, Rainbow (Plotly)
• All colormaps