[Radiance-general] calculating CRI and CCT

[John Mardaljevic]

Hi Chris,

The basic data and procedure for calculating CRI, CCT and others can be gleaned from this Matlab procedure:

http://www.lrc.rpi.edu/programs/nlpip/lightinganswers/lightsources/scripts/NLPIP_LightSourceColor_Script.m

Extrapolating from RGB to the required resolution is probably not for the squeamish.  I was going to try out the above-linked code to compare (Matlab) computed CRI & CCT with what the MK350 was giving me, but never got round to it.  For me, one of the 'take home' messages from tinkering with the MK350 (assuming the values are correct) was not to give too much importance to CRI or CCT alone -- much more informative to have the pair.  Better still, of course, the spectrum.

The SAGE Glass White Paper is available here:

http://sageglass.com/wp-content/uploads/2011/08/How_to_maintain_neutral_daylight_illumination_wtih_SageGlass_EC_Glazing.pdf

A journal paper on same has been accepted for publication by LR&T.

Cheers
John

John Mardaljevic PhD FSLL
Professor of Building Daylight Modelling
School of Civil & Building Engineering
Loughborough University
Loughborough
Leicestershire
LE11 3TU, UK

Tel: +44 1509 222630 (Direct)
Tel: +44 1509 228529 (Pam Allen, secretary)

j.mardaljevic at lboro.ac.uk<mailto:j.mardaljevic at lboro.ac.uk>

http://www.lboro.ac.uk/departments/civil-building/staff/mardaljevicjohn

Personal daylighting website:
http://climate-based-daylighting.com

[cid:C466B438-CE0B-488D-A45B-024218BA7A1E at lboro.ac.uk]

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://www.radiance-online.org/pipermail/radiance-general/attachments/20150226/d889b1a4/attachment-0001.html>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: RAEng-vector.png
Type: image/png
Size: 17432 bytes
Desc: RAEng-vector.png
URL: <http://www.radiance-online.org/pipermail/radiance-general/attachments/20150226/d889b1a4/attachment-0001.png>