Iray (silly?) question

Elettrodado

Hello,

Does Iray renders just the frame or the whole set?

Supposing I need to just render a face portrait, if I setup a whole scene with props that are not in the frame, will Iray be slower because it renders also the props not in the frame?

For istance, room parts that are not in the frame, will slow the render?

Thanks

mclaugh

Just elements in the frame, although light will interact (reflection, glare, shadow casting, etc.) with elements outside the frame, which will affect rendering time.

FSMCDesigns

Yes, items not in the frame will still affect the render process

WendyLuvsCatz

answering the second part of your question 

yes

because of the rays interacting and the geometry being loaded on the card and textures also use extra RAM even if not actually using more iterations 

however one needs to be choosy what they remove, rendering a figure pantless and without boots for an upper torso shot is logical but walls etc are needed to have a room render correctly, or a tree to cast a dappled leaf crown shadow etc, but if its a prop or tree etc not impacting on the visible scene you should delete it.

Richard Haseltine

It depends what you mean - as mclaugh says all elemnts in the scene are sent to the render engine, so that they can have their due effect (shadows, reflections, bounced light) so yes the out-of-shot elements have an impact on memory use, and will slow things at least a bit compared to a figure floating in space as paths that would run to infinity as they went away from the isolated figure will hit the walls of the room or props in the room if present, and will then potentially bounce off and require another round of calculation.