Creating light cones for internal shot

[noelyone]

Hi guys,

I am half way through rendering internal shots for a dougnut shop but cannot seem to work out how to create actual 'light streak paths' coming out of ceiling lights! Yes, light comes out but how can I actually see some kind of faded light cone...... it would really add to the drawing I'm producing!

I've tried all kinds of techniques including adding ies profiles but it hasn't done the trick! Any ideas? Or is this not possible in indigo yet?

Many thanks in advance!

PS. I'd also be grateful for any other ideas to improve the image!

Noel

[StompinTom]

If you mean like a volumetric fog effect, then make a cube that covers the whole interior and give it a slightly scattering material. That way you'll get a nice light streak effect.

[noelyone]

Hi, thanks for replying.

I don't want to create a mist inside the room as that will overshadow the elements of the room. I simply want some visible light to come out of the many circular ceiling lights - similar to the image attached.

If I'll get that result from your message then I'll give it a go - On that subject, by creating a cube that covers the whole interior, won't that hide everything in the room? you've said 'give it a scattering material' - I'm not 100% sure what you mean by this?
.

[Frutiger]

If you use a light mist that encompasses the entire room, you'll still get interior details and you'll also get the effect you're going after. What you're seeing in that picture you attached is essentially light being scattered by particles that are suspended in mid air, so you'll need to get some dust up in that hizzouse if you want to replicate that effect.

Here's a link to what I think is called a sub surface scattering material. If you take that and put it on a large box, you'll essentially get a small amount of fog or dust in the room. There's a link on that material page that will do a much better job explaining that technical details than I will.

It requires some fiddling, but I've gotten them to work pretty well in the past.

[dag]

To see the light path you'll need dust/fog whatever. Try http://www.indigorenderer.com/materials/materials/125
If you want a smaller light spot, try with a more narrow cylinder around the light source, or put the light higher up so the light doesn't spread out too much. Turn off the rest of the lights while testing.

[StompinTom]

That effect is created by the light being scattered by dust/fog. You don't need a very highly scattering/absorbing material, it won't really affect the visibility of your scene that much since the light its much brighter than the objects.

- Make a specular material
- Set the IOR to 1.0 so that it doesn't refract anything
- Enable Subsurface Scattering
- Select Uniform scattering
- Set the Scattering coefficient to about 0.01 (play with this, depends much on your scene)

The cube won't block your scene because it will be transparent with the above material.

[noelyone]

Guys that is all great help, many thanks to you all.

I'll spruce up the image in the next few days and post.
Ta.