# Questions about Electric Lighting Example

Hi all,

I am doint the Electric Lighting Example, but there are some things tha are unclear to me.

1. When you orientate the lights using points, does the distance between source and aim points play a role in the results you get?

2. When you use the orientation and tilt params, what is the rotation direction for both?

3. Why am I getting this result? Is it because aim points could be in a messed up order in connection to source points? Is it because of the length between the 2 points? Something else entirely?

4. If I have 2 meshes as geometry I want to use, how do you “combine” them?

5. How can I get the legend to appear and show me results in the falsecolor gif?

6. What kind of geometry is needed in order to display the Luminaire Web, Axes and Poly?

I am eager to learn so I will be very thankfull to anyone can poitn me in the right direction, be it by answering or showing me where and what to read.

Hi Hristo,

I’ll address the questions in order. If I cannot answer a question I will try to breakdown exactly why I cannot.

Q1. When you orientate the lights using points, does the distance between source and aim points play a role in the results you get?
A1. Could you post a screenshot of what “aim” you refer to. If “aim” refers to an indicator of surface orientation, and that indicator is visually distant from the surface assigned the lamp material, then probably not.

Q2: When you use the orientation and tilt params, what is the rotation direction for both?
A2: I believe this question refers to the direction honeybee sets as the default orientation of a lamp IES file. View the lamp in the Rhino 6 “top view” to determine the correct orientation. I believe Rhino 6/Honeybee by default renders the lamp such that the “top view” displays the lamp rotation with respect to the x axis. Finally, the lamp illuminated surface is on the bottom of a surface, facing the negative z axis.

3Q: Why am I getting this result? Is it because aim points could be in a messed up order in connection to source points? Is it because of the length between the 2 points? Something else entirely?
3A: Um… what result exactly?

4Q. If I have 2 meshes as geometry I want to use, how do you “combine” them?
4A. Perhaps render the surfaces as a single surface in Rhino 6 and then assign the geometry as a mesh in Honeybee? I have never attempted rendering a non-flat or discontinuous mesh.

5Q. How can I get the legend to appear and show me results in the falsecolor gif?
5A. Based on the other couple of forums on this topic, install Radiance 5.1

6Q. What kind of geometry is needed in order to display the Luminaire Web, Axes and Poly?
6A. If your question is what kind of inputs drawLuminaireWeb, drawLuminaireWeb, drawLuminaireAxis, and drawLuminairePoly takes, the answer is that drawLuminaireAxis takes a float or an ‘true’ booleen, and drawLuminairePoly takes a float or ‘true’ booleen. If your question is what kind of file you need to pass into the IES Luminaire panel, the answer is a .ies filetype.

Max

Hello Max,

wow, thank you very much for the detailed answers and your time.

The results I get from my model and simulation tend to vary, depending on the the chosen view, but my main problem is that I get some “anomalies”. I have all my lights hidden behind a metal facade, aiming at my volume. However I get this “spots” from somewhere or something, that don’t seem logical to me.

As for the _drawLuminaire parts, I know how to “turn them on”, but don’t know how to get the result to display. Will it be visible when I select the IES_Luminaire panel, or do I need to connect the Luminaire GEO to some kind of grasshopper geometry in order to get it displayed. This is so that I can check if my lights are pointed correctly.

In this screenshot you can see the moethod I use for orienting the lights. Using “aim” points.

After many unsatisfying attempts, I stardted to wonder whether the way I used to point my lights could be whats confusing the calculation in anyway. Is the distance from light to aim point relevant to how bright/dark my lights are? Is it correct to have an aiming point “inside” the mesh of my volume? Could selecting all points for my lights and then selecting all points for aiming mess up in some way how grasshopper reads the data?

Thank you very much for your time, I really appreciate it!

Hristo

And now, out of nowhere I get a fatal error(truncated octree) in my _runDA panel and the GIFs are missing in my ladybug\imagebasedSimulation folder? Any advice?