OTOY Forums

Can anyone explain to me how I use IES lighting. Frankly the manual is useless with 16 words dedicated to the subject.

I have set my distribution node to Image but there is no option to select an .IES file. So I assume that I am doing something wrong?

Thanks

hey steve,

you must just load the ies file as floatimage.

cheers,

dave

BIG thanks. I knew it must be something simple.

Roeland has explained it in the 2.45 release description:

"I'll clarify the changes in the light system:

To specify a directional light source, assign a texture to the distribution pin of the emitter. For images the distribution is given in latitude-longitude mapping, for the solid texture generators (like turbulence) it will project the light direction on an unit sphere. To load an IES file, use a floatimage; the file picker will allow you to load an IES file.

An emitter is assigned to a material input from the mesh node. If you assign the same material to multiple objects in the scene, Octane will consider them one emitter, so they will have the same distribution and orientation. Also the power specified in the emission node will be the total power emitted by all those objects. To assign different distributions or orientations to each emitter you need to assign a different material to each one.

Unfortunately this change is not backward compatible with the previous system (which specifies the emitted power per unit of area), so you'll have to tweak your light sources for the new beta."