[Radiance-general] Ellipsoidal Spotlight ies file

[Alexa I. Ruppertsberg]

Hi Rob,

sounds fine to me. No, you don't need to double the numbers, as your 
numbers correspond to one half of the spotlight cone (0 deg = centre of 
spotlight to 5 deg).
I played around with the lumens number and did not find that it was 
affecting anything.

good luck!

alexa

Fitzsimmons, Rob wrote:

> I hope I'm doing this correctly.. can anyone give me some advice?
> I'm modeling a Source 4 10 degree ellipsoidal spotlight
> On the web, I found this pdf which contains photometric data
> http://www.productionadvantageonline.com/pdf_files/410.pdf
> 
> By looking at the cosine curve on page 2, I gathered these numbers - degrees
> vs candela
> 0           .5          1            1.5         2           2.5         3
> 3.5         4           4.5         5            5.4   90.00
> 82000 81000  80000  76000   70000  62000   53000 45000   36000  27000
> 16000   0      0
> I'm not sure if I should double the angles - in that the chart goes from 0
> to 5, yet this is a 10 degree light
> 
> from the table on the upper right of page 2,
> 750 Watt lamp -- 21900 lumens (tho I guess eis2rad doesn't use this number?)
> 
> So I put it into a eis file like this:
> TILT=NONE
> 1    21900    1    12  1  1  1 -.6 0 0
> 1 1 750
> 0     .5     1      1.5     2      2.5     3     3.5     4     4.5     5
> 5.4   90.00
> 82000 81000  80000  76000   70000  62000   53000 45000   36000 27000   16000
> 0     0
> 
> I left my RwR book at home, so I don't remember the meaning of all the other
> numbers.
> Does this seem correct? Since this is the first time I've tried doing this,
> I mostly want to know if I'm looking for the right numbers, and using them
> correctly
> 
> Thanks, Rob Fitzsimmons
> 
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-- 
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Dr. Alexa I. Ruppertsberg
Department of Optometry
University of Bradford
Bradford
BD7 1DP
UK

Phone: 	++44 (0) 1274 - 23 53 78
email: 	a.i.ruppertsberg at bradford.ac.uk
web:	www.staff.brad.ac.uk/airupper
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