View Full Version : help with lighting

05-09-2012, 02:41 PM
hello, i'm trying to recreate a LED strip and not having much luck. they need to light up a certain space and need to be directional (not light the area behind them). anyone have any idea of the best way to accomplish this?

it's an arch vis rendering so it needs to look as accurate as possible.

i've included a pic of the lights that will be used in the actual build of the piece.

05-09-2012, 02:46 PM
It looks like those are individual LEDs in a transparent rubber hose, so they will light all around. You just need to make sure that you don't have any light leaking from where you don't want it to.


05-09-2012, 02:55 PM
yes, they're individual on a strip. the strip is opaque.

do i need to use individual lights for each LED? i've tried several different light types and can't seem to get the lighting i need.

i need to light the interior section of the shelf unit. the LED strips will be mounted in the top and faced down.

05-09-2012, 03:24 PM
Will the strip be visible? I would say that yes, you probably do want a light for each bulb as I would imagine they each give off their own lightcone? You could go oldskool with individual spots, slightly modernise with sphericals or if you have the data needed you could even go all the way with IES...


05-09-2012, 03:36 PM
Either you use a bunch of lights (Point lights would render fastest, but have hard shadow... sphericals would be more realistic)...

Or... You could model the "bulbs" and make them particularly luminous. Then use radiosity (probably Monte Carlo). This is slow, but would look awesome if you need closeup details.

The light route has the advantage of being able to render out a pass of lens flares (at least the twinkling glowing kind, not necessarily the gratuitous bunch of internal reflections kind) pretty easily. You could use luxigons in Modeler to set them up.

05-09-2012, 03:38 PM
If you won't actually see the light strips then just put some bulbs in a line up there, or even use a tube light. Those strip lights probably illuminate fairly evenly at a distance.

Whichever lights you use you will want to enable falloff (most like inverse squared). Then set the range pretty small and crank up the intensity to get the good falloff.

05-09-2012, 03:40 PM
i searched for the IES but no luck. i guess i'll try luxigons. it just seems like a lot of work. :grumpy:

05-09-2012, 03:44 PM
You might also try a single Area Light and then put a Gobo under it that is a flat plane with holes in it in a line. The holes let the light through like the bulbs. Then you have just one light. You may need more light samples for the shadows, though. Still... use falloff...

05-09-2012, 03:57 PM
eh, i just recessed the top and stuck sphericals in there. i have an actual strip of the green lights to show the client.

05-09-2012, 04:34 PM
I gave this a go. just make a bunch of luminous polygons hidden to the camera and let radiosity do it's thing. Well it's a bit more complicated than that but that's the general idea.