colour.temperature.uv_to_CCT_Ohno2013(uv, cmfs=None, start=1000, end=100000, count=10, iterations=6)[source]

Returns the correlated colour temperature \(T_{cp}\) and \(\Delta_{uv}\) from given CIE UCS colourspace uv chromaticity coordinates, colour matching functions and temperature range using Ohno (2013) method.

The iterations parameter defines the calculations precision: The higher its value, the more planckian tables will be generated through cascade expansion in order to converge to the exact solution.

  • uv (array_like) – CIE UCS colourspace uv chromaticity coordinates.

  • cmfs (XYZ_ColourMatchingFunctions, optional) – Standard observer colour matching functions, default to the CIE 1931 2 Degree Standard Observer.

  • start (numeric, optional) – Temperature range start in kelvins.

  • end (numeric, optional) – Temperature range end in kelvins.

  • count (int, optional) – Temperatures count in the planckian tables.

  • iterations (int, optional) – Number of planckian tables to generate.


Correlated colour temperature \(T_{cp}\), \(\Delta_{uv}\).

Return type





>>> from pprint import pprint
>>> from colour import MSDS_CMFS, SPECTRAL_SHAPE_DEFAULT
>>> cmfs = (
...     MSDS_CMFS['CIE 1931 2 Degree Standard Observer'].
...     copy().align(SPECTRAL_SHAPE_DEFAULT)
... )
>>> uv = np.array([0.1978, 0.3122])
>>> uv_to_CCT_Ohno2013(uv, cmfs)  
array([  6.50747...e+03,   3.22334...e-03])