Why Aren’t Instanced /copied Lights Rendering?

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Hi everyone,

I’m trying to understand an issue I’m having with lights in Houdini.

I have created points arranged around a circle and am instancing/copying lights onto those points. The lights appear correctly in the viewport, but when I render the scene, the instanced/copied lights don’t seem to contribute any illumination to the render.

I’m trying to figure out whether this is:

* A limitation of instancing/copying lights onto points
* A rendering/lighting setup issue on my side
* A known bug
* Or something specific to the renderer I’m using


Has anyone encountered this behavior before? If so, could you explain what is actually happening and what I might be missing?

I’d also appreciate a workaround or the recommended way of creating multiple lights distributed around a circle while still having them contribute properly to the render.

One other question: would the same approach work if, instead of lights, I used emissive objects/materials (for example, small emissive geometry copied/instanced around the circle)? If so, are there any important differences in how the renderer treats emissive geometry versus actual light objects?

If possible, I’d really appreciate an explanation of the underlying reason rather than just a workaround, as I’d like to understand how Houdini handles instanced lights during rendering.

Thanks!
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Edited by gregjenings - 2026年10月1日 09:42:12

Attachments:
Point_Light_Instancing.hip (621.9 KB)

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because you load your points into the stage, they shadow your pointlight. either dont load them or prune them
Edited by ronald_a - 2026年10月2日 07:17:15
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ronald_a
because you load your points into the stage, they shadow your pointlight. either dont load them or prune them
Image Not Found


Thank you, Ronald. You were correct to point out the issue, and it worked!

I am now facing another issue regarding animating the light intensity in a particular sequence. So far, this is what I have managed to achieve, and I’m sharing the .hip file here for reference.

Unfortunately, the intensity is not animating as expected, and I’m also unable to view the render output.

Any suggestions or an alternative method to achieve this would be highly appreciated.

Thank you in advance for your help!
Edited by gregjenings - 2026年10月2日 09:30:47

Attachments:
Animating Lights.hip (713.6 KB)

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Hello, I got your file working. I object merged the points inside the copytopoints and changed it to use "Internal SOP" as the point source. I don't know the reason why this works and your method didn't, maybe something to do with how the attribute is translated from the sopcreate.

Hopefully someone who knows Solaris better can chime in with an answer.

EDIT: Found this thread: https://www.sidefx.com/forum/topic/100624/ [www.sidefx.com]
Sounds like a limitation with copytopoints currently.
Edited by freshbaked - 2026年10月2日 12:42:23

Attachments:
Animating Lights Fix.hiplc (708.5 KB)

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