Light falloff?

[Rikk The Gaijin]

It might sounds like a stupid question, but how do you set the light falloff? Octane doesn't have spotlights, so if I have a plane or a sphere with an emitter material, how do I achieve this?

[gordonrobb]

I was under the impression Octane couldn't do this because of it's "physically accurate" nature - except by using ies lights.

Will be interested to find out otherwise though

[dionysiusmarquis]

Maybe with a rough specular Object in front of the light?

[UnCommonGrafx]

I would try ies first.
Secondly, or in conjunction, I would build a light shade that had an adjustable iris/hole to do fstop-like sizing. I'm thinking stage light: how do they get that softness and hardness of a light?
(Chuckle, an "essential" question for curriculum mapping. Oh gosh, it's becoming ingrained!! </offpoint>)

In another renderer, it worked for me; since this is 'limited' to physical accuracy, this ought to be quick work.

Placing a light inside the above shade would essentially give you a spotlight. They don't need to make one, really.


In addition:
If you make morphs for your light shade, realllly small, and as large as possible, then you can change this based on a slider.
The light shade needs to be 'light-tight', pun intended.
A morph based on length of the shade, to elongate and shorten the barrel/placement of light near the opening, would allow other effects.
This sounds kinda cool with Octane in mind...

[dionysiusmarquis]

Nice idea. I tried to reconstruct a spotlight. To get hard light edges you just need to decrease the light source size. WIth a cone and some booleans I got this (I marked the light source red and made the cone transparent to show the hole):

Edit: The Spotlight radius increases with light smoothness even when the distance of the cones bottom and light source is consistent. The cone setup can be much simpler: Just keep the cone open at the bottom and control the cone radius to change the spotlight radius (no resizeable hole needed).

[Tugpsx]

Will be a part of upcoming script.

Hollywood

MeshLights

[gordonrobb]

Tht looks like a great solution.