[Radiance-general] December Illuminance values.

[Greg Ward]

This may be a sampling issue.  Look at a plan view of the workplane  
at the problem times -- it may be that the sensor is seeing direct  
sun in one case and not in the other.  Even the tiniest change in  
geometry can result in a huge change in value if this is the case.

-Greg

> From: G V DEEPAK <deepak.gv at ufl.edu>
> Date: April 17, 2009 3:59:23 PM PDT
>
> Hello Everyone,
>
> I am involved in simulation on venetian blinds (using mkillum for - 
> ab 1). We are performing comparison for two sets of blinds, one is  
> the normal conventional horizontal blinds and the other one is the  
> split blinds in which the the blinds system is split into three  
> equal parts. when measuring illuminance values for year long  
> simulations . I observe that we get large errors in values in  
> December  varying from 10% to 60% ( difference in values between  
> conventional and split blinds though they are at the same angle and  
> same geometry) I observe these disturbances only in the month of  
> December and at the sensor point closest to the window. Is this  
> kind of error normal..?
>
> Thank you
>
> G V Deepak
> Gainesville, Florida