What color is a blackbody?
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The idea: It would be nice to know what color a blackbody is at various temperatures.
Here is some help on converting blackbody temperature to color pixel rgb values.
1000 K #ff3800 1200 K #ff5300 1400 K #ff6500 1600 K #ff7300 1800 K #ff7e00 2000 K #ff8912 2200 K #ff932c 2400 K #ff9d3f 2600 K #ffa54f 2800 K #ffad5e 3000 K #ffb46b 3200 K #ffbb78 3400 K #ffc184 3600 K #ffc78f 3800 K #ffcc99 4000 K #ffd1a3 4200 K #ffd5ad 4400 K #ffd9b6 4600 K #ffddbe 4800 K #ffe1c6 5000 K #ffe4ce 5200 K #ffe8d5 5400 K #ffebdc 5600 K #ffeee3 5800 K #fff0e9 6000 K #fff3ef 6200 K #fff5f5 6400 K #fff8fb 6600 K #fef9ff 6800 K #f9f6ff 7000 K #f5f3ff 7200 K #f0f1ff 7400 K #edefff 7600 K #e9edff 7800 K #e6ebff | 8000 K #e3e9ff 8200 K #e0e7ff 8400 K #dde6ff 8600 K #dae4ff 8800 K #d8e3ff 9000 K #d6e1ff 9200 K #d3e0ff 9400 K #d1dfff 9600 K #cfddff 9800 K #cedcff 10000 K #ccdbff 10200 K #cadaff 10400 K #c9d9ff 10600 K #c7d8ff 10800 K #c6d8ff 11000 K #c4d7ff 11200 K #c3d6ff 11400 K #c2d5ff 11600 K #c1d4ff 11800 K #c0d4ff 12000 K #bfd3ff 12200 K #bed2ff 12400 K #bdd2ff 12600 K #bcd1ff 12800 K #bbd1ff 13000 K #bad0ff 13200 K #b9d0ff 13400 K #b8cfff 13600 K #b7cfff 13800 K #b7ceff 14000 K #b6ceff 14200 K #b5cdff 14400 K #b5cdff 14600 K #b4ccff 14800 K #b3ccff 15000 K #b3ccff 15200 K #b2cbff 15400 K #b2cbff 15600 K #b1caff 15800 K #b1caff | 16000 K #b0caff 16200 K #afc9ff 16400 K #afc9ff 16600 K #afc9ff 16800 K #aec9ff 17000 K #aec8ff 17200 K #adc8ff 17400 K #adc8ff 17600 K #acc7ff 17800 K #acc7ff 18000 K #acc7ff 18200 K #abc7ff 18400 K #abc6ff 18600 K #aac6ff 18800 K #aac6ff 19000 K #aac6ff 19200 K #a9c6ff 19400 K #a9c5ff 19600 K #a9c5ff 19800 K #a9c5ff 20000 K #a8c5ff 20200 K #a8c5ff 20400 K #a8c4ff 20600 K #a7c4ff 20800 K #a7c4ff 21000 K #a7c4ff 21200 K #a7c4ff 21400 K #a6c3ff 21600 K #a6c3ff 21800 K #a6c3ff 22000 K #a6c3ff 22200 K #a5c3ff 22400 K #a5c3ff 22600 K #a5c3ff 22800 K #a5c2ff 23000 K #a4c2ff 23200 K #a4c2ff 23400 K #a4c2ff 23600 K #a4c2ff 23800 K #a4c2ff | 24000 K #a3c2ff 24200 K #a3c1ff 24400 K #a3c1ff 24600 K #a3c1ff 24800 K #a3c1ff 25000 K #a3c1ff 25200 K #a2c1ff 25400 K #a2c1ff 25600 K #a2c1ff 25800 K #a2c1ff 26000 K #a2c0ff 26200 K #a2c0ff 26400 K #a1c0ff 26600 K #a1c0ff 26800 K #a1c0ff 27000 K #a1c0ff 27200 K #a1c0ff 27400 K #a1c0ff 27600 K #a1c0ff 27800 K #a0c0ff 28000 K #a0bfff 28200 K #a0bfff 28400 K #a0bfff 28600 K #a0bfff 28800 K #a0bfff 29000 K #a0bfff 29200 K #a0bfff 29400 K #9fbfff 29600 K #9fbfff 29800 K #9fbfff |
Here is a more detailed table which includes chromaticity values and such.
If you can see this line, then its background isn't black, so the table above probably lacks color. Sorry. Perhaps you have an old browser?
The black body spectrum was mapped to the CIE XYZ color space for integration using the CIE 1964 10-deg color matching functions. The XYZ to RGB conversion was done with sRGB's primaries and gamma correction, and a D65 whitepoint. A blackbody color tool hack was used to create a colorized datafile, and a plain text one.
Update (2016-Mar-30): For most applications where a human is looking at a screen, and thus judging colors against screen white, a nonstandard but white D58 whitepoint is preferable to a standard but bluish D65 whitepoint. A modified blackbody color tool hack was used to create a colorized datafile for sRGB primaries and gamma, but substituting a nonstandard D58 whitepoint for sRGB's D65. Using some CMF files carelessly grabbed from the web. This datafile was just a quick kludge, with no quality control. End of update.
Please let me know if 1976 u'v' chromaticity coordinates would be more useful than these 1931 x y ones.
Why did I hack out my own program when foo existed?
Mainly because different authorities were claiming different results,
and there is nothing like rolling your own to make sure you understand
what is going on. Feel free to email links to your favorite foo,
and I'll add them below.
specrend doesn't use D65
(so the RGB values are odd).
Thanks
My thanks to John Walker's Colour Rendering of
Spectra (specrend) and Dan Bruton's Color
Science, who's pages got me started. To the CVRL Color & Vision
database. To Andrew Hamilton for What
colour is the Sun?, which suggested I was not completely confused.
And to efg for his Color
Reference Library. Without them, this page would not have
happened.
Notes:
Doables:
Say Plank. What else?
Include u'v' 1976 chromaticity coordinates.
Principled low bound. Rod-ed graying out? sRGB's 80 cd/m^2 monitor?
Javascript K to color mapper.
curves and code
History:
2016-Mar-30 Added a D58 file.
2002-Nov-11 Fixed links broken by CVRL move. Added a link.
2001-Jun-22 Switched to sRGB from Rec.709
(same primaries, similar matrix, different gamma correction).
2001-Jun-04 on-line