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<p class=MsoNormal><span style='font-size:10.0pt;font-family:"Arial","sans-serif";
color:#1F497D'>It would help to know your command process for calculating
illuminance and daylight factor to troubleshoot.<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:10.0pt;font-family:"Arial","sans-serif";
color:#1F497D'><o:p> </o:p></span></p>
<p class=MsoNormal><span style='font-size:10.0pt;font-family:"Arial","sans-serif";
color:#1F497D'>Also, if your rpict/rtrace ambient sampling settings are not
stringent enough, differences could be due to random sampling variation between
two different calculation runs.<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:10.0pt;font-family:"Arial","sans-serif";
color:#1F497D'><o:p> </o:p></span></p>
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<p class=MsoNormal><b><span style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'>From:</span></b><span
style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'>
radiance-general-bounces@radiance-online.org
[mailto:radiance-general-bounces@radiance-online.org] <b>On Behalf Of </b>Victor
Li<br>
<b>Sent:</b> Thursday, December 10, 2009 4:04 AM<br>
<b>To:</b> Radiance general discussion<br>
<b>Subject:</b> [Radiance-general] Daylight factor<o:p></o:p></span></p>
</div>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>Dear:<br>
<br>
Daylight factors are expressed as the percentage of natural light falling on a
work surface compared to that which would have fallen on a completely
unobstructed horizontal surface under exactly the same sky conditions. Thus, a
daylight factor of 5% on an internal surface means that it received only 1/20th
of the maximum available natural light.<br>
<br>
so we can calculate daylight factor by RADIANCE with a overcast sky. Then i
calculated the illuminance under overcast sky. I found the distribution of
illuminance and skyfactor in the room is different. For example, in the room
ratio of minimum to average of daylight and illuminance are quite different.
Would you tell me the reason?<br>
<br>
Best Regards!<o:p></o:p></p>
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