What the heck are AOVs?


#1

Can someone please explain to me in the simplest terms possible, what an AOV is how/if AOV differs from render passes/exr layers?

Sorry if this is a stupid question.


#2

From my understanding they are exactly the same thing.

Sometimes people refer to AOVs when they are actually talking about utility passes though (Like normal pass, UV pass, etc.)


#3

this might help…

renderman does split AOVS and LPES
https://renderman.pixar.com/resources/current/RenderMan/risAOVs.html
https://renderman.pixar.com/resources/current/RenderMan/risLPEs.html

also in arnold the called AOVs
https://support.solidangle.com/display/AFMUG/AOVs

vray does call them renderelements
http://docs.chaosgroup.com/display/VRAY3MAYA/Render+Elements

in redshift they are calles AOVs or render channels
http://docs.redshift3d.com/Default.html#I/AOVs aka Render Channels.html

iray light path expressions…
http://blog.irayrender.com/post/37260056351/instant-relighting-nonphysical-effects


#4

They get referred to as AOVs (Arbitrary Output Variable) or Secondaries rather than layers or passes quite often - but it depends where you work. You’d use Primary to describe the main RGB output of the render.

Layers/Passes are used to break the different objects in your scene into different renders.

For myself, utility passes as a type of pass which only contains “data” AOVs (normals, positions, deeps, etc) and doesn’t contain any lighting or shading info.

Beauty pass would be used to describe a pass which has lighting and shading info in it.


#5

Very solid response.