colour.temperature.uv_to_CCT_Ohno2013(uv: ArrayLike, cmfs: Optional[MultiSpectralDistributions] = None, start: Optional[Floating] = None, end: Optional[Floating] = None, count: Optional[Integer] = None, iterations: Optional[Integer] = None) NDArray[source]#

Return 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 (ArrayLike) – CIE UCS colourspace uv chromaticity coordinates.

  • cmfs (Optional[MultiSpectralDistributions]) – Standard observer colour matching functions, default to the CIE 1931 2 Degree Standard Observer.

  • start (Optional[Floating]) – Temperature range start in kelvin degrees, default to 1000.

  • end (Optional[Floating]) – Temperature range end in kelvin degrees, default to 100000.

  • count (Optional[Integer]) – Temperatures count/samples in the planckian tables, default to 10.

  • iterations (Optional[Integer]) – Number of planckian tables to generate, default to 6.


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])