colour.models.log_encoding_CanonLog3¶

colour.models.log_encoding_CanonLog3(x, bit_depth=10, out_legal=True, in_reflection=True)[source]¶

Defines the Canon Log 3 log encoding curve / opto-electronic transfer function.

Parameters:	x (numeric or array_like) – Linear data \(x\). bit_depth (int, optional) – Bit depth used for conversion. out_legal (bool, optional) – Whether the Canon Log 3 non-linear data is encoded in legal range. in_reflection (bool, optional) – Whether the light level \(x\) to a camera is reflection.
Returns:	Canon Log 3 non-linear data.
Return type:	numeric or ndarray

Notes

Introspection of the grafting points by Shaw, N. (2018) shows that the Canon Log 3 IDT was likely derived from its encoding curve as the later is grafted at +/-0.014:

>>> clog3 = 0.04076162
>>> (clog3 - 0.073059361) / 2.3069815
-0.014000000000000002
>>> clog3 = 0.105357102
>>> (clog3 - 0.073059361) / 2.3069815
0.013999999999999997

Notes

Domain	Scale - Reference	Scale - 1
`x`	[0, 1]	[0, 1]

Range	Scale - Reference	Scale - 1
`clog3`	[0, 1]	[0, 1]

References

[Can16]

Examples

>>> log_encoding_CanonLog3(0.18) * 100  # doctest: +ELLIPSIS
34.3389369...