# Blackbody (Plotly)

Canonical URL: https://colorcurio.us/colormaps/plotly.blackbody
Source type: Colormap
Type: sequential
Collection: plotly
Attribution: plotly.js / plotly.py contributors
License: MIT
Source: https://github.com/plotly/plotly.py/blob/main/_plotly_utils/colors/plotlyjs.py
Tags: thermal, astronomy
Stops: 256

## Summary

Blackbody (Plotly) is a sequential colormap from the plotly collection. Inspect its perceptual lightness, chroma, and hue profile on colorcurio.us.

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: https://colorcurio.us/colormaps/families/plotly
- All colormaps: https://colorcurio.us/colormaps