different results

hello.i am trying to simulate a lightshelf in the radiance.but radiance
gives differnt results each time i redraw my simulation zone. i should
mention that i draw the zone in the ecotect and export it to radiance. i
attached two files that everything is the same in them,but the illuminance
levels that radiance gives me are different. i would be grateful if you
could help me to resolve this problem
sincerely
Shailan

1a.zip (14.3 KB)

1.zip (14.2 KB)

Hi, Shailan, can u read on the "-u" option of the rtrace program menu? Not
sure if you should try the "-u+" specification ...

- Ji

在 2012年11月4日星期日,shailan zareiy 写道:

···

hello.i am trying to simulate a lightshelf in the radiance.but radiance
gives differnt results each time i redraw my simulation zone. i should
mention that i draw the zone in the ecotect and export it to radiance. i
attached two files that everything is the same in them,but the illuminance
levels that radiance gives me are different. i would be grateful if you
could help me to resolve this problem
sincerely
Shailan

thank you Ji, but unfortunately changing the -u option didn't change the
result

···

On Sun, Nov 4, 2012 at 7:06 AM, Ji Zhang <[email protected]> wrote:

Hi, Shailan, can u read on the "-u" option of the rtrace program menu? Not
sure if you should try the "-u+" specification ...

- Ji

在 2012年11月4日星期日,shailan zareiy 写道:

hello.i am trying to simulate a lightshelf in the radiance.but radiance
gives differnt results each time i redraw my simulation zone. i should
mention that i draw the zone in the ecotect and export it to radiance. i
attached two files that everything is the same in them,but the illuminance
levels that radiance gives me are different. i would be grateful if you
could help me to resolve this problem
sincerely
Shailan

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Radiance-general mailing list
[email protected]
http://www.radiance-online.org/mailman/listinfo/radiance-general

Dear Shailan,

it will be difficult to help you with this:

1) We do not really know the problem. What means different results - are we talking about 1000%, 10%, 0.1%?

2) We do not know the scene (model) and simulation paramaters. Do you use a mirror (secondary light source), is direct sun considered, are you modeling the sun (if it is existing in the model) by a small light source or as contribution to Tregenza patches...? You attached some .eco-files, which probably can be opened in Ecotec, but as a Radiance user I cannot even open those.

So my advice: Give a really clear description of the problem, and provide us with information to reproduce it. E.g. a Radiance scene description together with the parameters you are using.

Cheers, Lars.

Just a side-note to this: It is good etiquette to post your scene and related files at a website rather than attaching them to your e-mail. Most e-mail programs will strip attachments, and we need to be considerate of those who pay for storage or have slow connections.

Best,
-Greg

···

From: "Lars O. Grobe" <[email protected]>
Date: November 4, 2012 6:56:35 AM PST

Dear Shailan,

it will be difficult to help you with this:

1) We do not really know the problem. What means different results - are we talking about 1000%, 10%, 0.1%?

2) We do not know the scene (model) and simulation paramaters. Do you use a mirror (secondary light source), is direct sun considered, are you modeling the sun (if it is existing in the model) by a small light source or as contribution to Tregenza patches...? You attached some .eco-files, which probably can be opened in Ecotec, but as a Radiance user I cannot even open those.

So my advice: Give a really clear description of the problem, and provide us with information to reproduce it. E.g. a Radiance scene description together with the parameters you are using.

Cheers, Lars.

thank you for your response,I attached two radiance files, unfortunately i
couldn't find where i can send my files from the site.
the difference is 100% or some times more,i attached radiance files,the
light shelf i use has 90% reflectance that should cause increase of
illuminance in the back of the room, but it in rad1 file it is decreased,
and in the rad 2 file it is increased.
I hope these discription would be enough

rad2.zip (576 Bytes)

rad1.zip (479 Bytes)

···

---------- Forwarded message ----------
From: shailan zareiy <[email protected]>
Date: Sun, Nov 4, 2012 at 8:13 PM
Subject: Re: [Radiance-general] different results
To: Radiance general discussion <[email protected]>

On Sun, Nov 4, 2012 at 6:26 PM, Lars O. Grobe <[email protected]> wrote:

Dear Shailan,

it will be difficult to help you with this:

1) We do not really know the problem. What means different results - are
we talking about 1000%, 10%, 0.1%?

2) We do not know the scene (model) and simulation paramaters. Do you use
a mirror (secondary light source), is direct sun considered, are you
modeling the sun (if it is existing in the model) by a small light source
or as contribution to Tregenza patches...? You attached some .eco-files,
which probably can be opened in Ecotec, but as a Radiance user I cannot
even open those.

So my advice: Give a really clear description of the problem, and provide
us with information to reproduce it. E.g. a Radiance scene description
together with the parameters you are using.

Cheers, Lars.

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http://www.radiance-online.**org/mailman/listinfo/radiance-**general<http://www.radiance-online.org/mailman/listinfo/radiance-general>

Hi Shailan,

you did not make the model available, so this is all guess-work. By the way, as Greg mentioned, we do not attach files on this email list, instead use some web- or ftp-space and embed a link into your mail, please.

What you had sent were the parameters used processing the model using Radiance tools (collected in rif-files for rad, the control program for scene processing). The only interesting difference I found in there was the scene extent. While I cannot find out whether my assumption is true or not, as I do not have access to the model, a different scene extent (geometry) could point us to a difference in the model geometry. I have no idea how the two rif-files were created, but if the software doing so did a good job, then one model starts at x=1 while the other starts at x=2. Not exactly identical models.

Maybe you find a way to put your model onto a ftp or website so that others can have a look at it. Aside, you could use objline or objview or any kind of scene previewer, rotate a bit, and check that there are no obstructions in front of one model's facade or any unwanted differences. You can also use getbbox on both radfiles - the bounding box for two identical geometries should be the same...

Cheers, Lars.

By the way, while your ZONE extends from z=0 to z=4, the view point for the plan views (c1) is at z=6. Again I wonder why. I hope you are not above the ceiling with your plan views...

Cheers, Lars.