Conversion of RGB irradiance values to a illuminance value

Dear list members,

I use hemi-spherical HDR images to compute a vertical irradiance value (W/m^2) for each color channel.

If I wish to compare/calibrate these numbers to a reading from a light meter (giving illuminance in Lux) how do I go about converting the three (RGB) irradiances to illuminance?



Claus B. Madsen

Assoc. Prof., Ph.D. | Department of Architecture and Media Technology

Phone: +45 9940 8788 | E-mail: | Web:

Aalborg University | Sofiendalsvej 11 | 9200 Aalborg SV | Denmark

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