Panoramic HDRI - Absolute Luminance Calibration

PANORAMIC HDRI - ABSOLUTE LUMINANCE CALIBRATION 2.0

colour-science.org - February 27, 2020

This file defines two Gizmos / Groups:

- Panoramic HDRI - Absolute Luminance Calibration: Performs absolute luminance calibration of panoramic HDRI images using Lagarde (2016) method.
- Panoramic HDRI - Analytic Light Source: Computes the illuminance value for an analytic light source accounting for the illuminance difference between two panoramic HDRI images and the light source position in the image using Lagarde (2016) method.

Note that the Panoramic HDRI - Analytic Light Source Gizmo / Group currently uses two hard copies of the Panoramic HDRI - Absolute Luminance Calibration Group, it is strongly advised to replace them with the Gizmo variant in the context of a studio deployment.

Latest version of the file will always be available at this url: https://github.com/colour-science/colour-nuke/blob/master/colour_nuke/scripts/panoramic_hdri_absolute_luminance_calibration.nk

A workflow example file is available at this url: https://github.com/colour-science/colour-nuke/blob/master/colour_nuke/scripts/panoramic_hdri_absolute_luminance_calibration_workflow_example.nk

[1] Lagarde, S., Lachambre, S., & Jover, C. (2016). An Artist-Friendly Workflow for Panoramic HDRI. Retrieved from http://blog.selfshadow.com/publications/s2016-shading-course/unity/s2016_pbs_unity_hdri_notes.pdf

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