[Radiance-general] Modelling sky using sky scanner MS-321LR

[John Mardaljevic]

Hi Ehsan,

Yes, that's right -- you simply scale the measured (circular patch) luminance or radiance values by the ratio of the 'rectangular' patch solid angle to the circular source solid angle, i.e. some factor > 1.  Your sky will of course not be continuous, but at least the total luminous output will be realistic.  See table 3-7, p70 in Chapter 3 here:

http://climate-based-daylighting.com/doku.php?id=resources:thesis

Another way is to use the measured data to create a 'brightdata' representation of the sky, which will be continuous.  How that is done is also described in Chapter 3.

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

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

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