IES file manipulation

Hi everyone,

I have a situation where I'm using ies2rad to bring files into
radiance. Only I want to attach the photometric info to illum surfaces
surrounding my detailed fixture geometry rather than to the default
geometry... (pretty typical I think) However in order to do so, I have
to add rectangles in order to "seal" my fixture. I am concerned that
the addition of these rectangles will affect the magnitude of the
photometric information.

I guess one way to not even deal with boxing the luminaire with illums
is to attach a negative value to the lamp's glow material. Then rays
won't "sneak out". Of course the lamps won't add internal illumination
in that case.

Any thoughts would be appreciated. I will try and run some tests when
I get a chance.

Thanks.

Mark

Hi Mark,

Did you try the -i option to ies2rad?

-Greg

···

From: "Mark de la Fuente" <[email protected]>
Date: June 24, 2004 12:08:51 AM CEST

Hi everyone,

I have a situation where I'm using ies2rad to bring files into radiance. Only I want to attach the photometric info to illum surfaces surrounding my detailed fixture geometry rather than to the default geometry... (pretty typical I think) However in order to do so, I have to add rectangles in order to "seal" my fixture. I am concerned that the addition of these rectangles will affect the magnitude of the photometric information.

I guess one way to not even deal with boxing the luminaire with illums is to attach a negative value to the lamp's glow material. Then rays won't "sneak out". Of course the lamps won't add internal illumination in that case.

Any thoughts would be appreciated. I will try and run some tests when I get a chance.

Thanks.

Mark

Greg, in this case I'm looking at a 20' linear fluorescent
Indirect/Direct pendant. The IES file is for a 4' section and I would
array it 5 times. A sphere with 2' diameter would probably not work if
the suspension length were less than 2' since this is a partially
indirect pendant.. Also, not sure if having the pendant poking through
the illum sphere would work.

I thought of a different way of handling this. Since the ies2rad
program creates the top and bottom rectangles in this case, why not just
use an illum material with a void modifier to create the edges of the
box?

Thanks for the response. It would certainly be faster to use the -i
option.

Mark

Hi Mark,

Did you try the -i option to ies2rad?

-Greg

From: "Mark de la Fuente" <MdelaFuente at wmtao.com>
Date: June 24, 2004 12:08:51 AM CEST

Hi everyone,

I have a situation where I'm using ies2rad to bring files into
radiance. Only I want to attach the photometric info to illum
surfaces surrounding my detailed fixture geometry rather than to the

default geometry... (pretty typical I think) However in order to do

so, I have to add rectangles in order to "seal" my fixture. I am
concerned that the addition of these rectangles will affect the
magnitude of the photometric information.

I guess one way to not even deal with boxing the luminaire with

illums

is to attach a negative value to the lamp's glow material. Then rays

won't "sneak out". Of course the lamps won't add internal
illumination in that case.

Any thoughts would be appreciated. I will try and run some tests

when

···

I get a chance.

Thanks.

Mark

Mark de la Fuente wrote:

Greg, in this case I'm looking at a 20' linear fluorescent Indirect/Direct pendant. The IES file is for a 4' section and I would array it 5 times. A sphere with 2' diameter would probably not work if the suspension length were less than 2' since this is a partially indirect pendant.. Also, not sure if having the pendant poking through the illum sphere would work.
I thought of a different way of handling this. Since the ies2rad program creates the top and bottom rectangles in this case, why not just use an illum material with a void modifier to create the edges of the box?

Hiya Mark,

Do you have the Rendering with Radiance book? there's a detailed example of using lboxcorr to create a rectangular shaped illum container for your IES distro. I think that's what you need. (?)

···

----

      Rob Guglielmetti

e. [email protected]
w. www.rumblestrip.org

Hi Mark,

That should work -- set the three real illum arguments to zero, though, so it won't try to contribute to the output.

-Greg

From: "Mark de la Fuente" <[email protected]>
Date: June 24, 2004 2:23:37 PM GMT+01:00

Greg, in this case I'm looking at a 20' linear fluorescent Indirect/Direct pendant. The IES file is for a 4' section and I would array it 5 times. A sphere with 2' diameter would probably not work if the suspension length were less than 2' since this is a partially indirect pendant.. Also, not sure if having the pendant poking through the illum sphere would work.

I thought of a different way of handling this. Since the ies2rad program creates the top and bottom rectangles in this case, why not just use an illum material with a void modifier to create the edges of the box?

Thanks for the response. It would certainly be faster to use the -i option.

Mark

···

> Hi Mark,
>
> Did you try the -i option to ies2rad?
>
> -Greg
>
> From: "Mark de la Fuente" <MdelaFuente at wmtao.com>
> Date: June 24, 2004 12:08:51 AM CEST
>
> Hi everyone,
>
> I have a situation where I'm using ies2rad to bring files into
> radiance. Only I want to attach the photometric info to illum
> surfaces surrounding my detailed fixture geometry rather than to the
> default geometry... (pretty typical I think) However in order to do
> so, I have to add rectangles in order to "seal" my fixture. I am
  > concerned that the addition of these rectangles will affect the
  > magnitude of the photometric information.
>
> I guess one way to not even deal with boxing the luminaire with illums
> is to attach a negative value to the lamp's glow material. Then rays
> won't "sneak out". Of course the lamps won't add internal
> illumination in that case.
>
> Any thoughts would be appreciated. I will try and run some tests when
> I get a chance.
>
> Thanks.
>
> Mark