DOF and holdout meshes?


#1

Is there any way to blur the holdout mesh geometry the same way as the particles? Without blurring we get sharp holdouts in a beautiful blurred rendering.


#2

I guess you would have to match the DOF in the renderer of your choice as well to match the matte…


#3

Well, this will not help if the matte object has a sharp corner in my krakatoa rendering. Imagine a sphere in the middle of a particle cloud. The sphere is a mesh and used as matte object. The particles have nice DOF whereas the edges of the sphere are aways sharp.


#4

I see, well thats a limitation I guess


#5

The holdouts themselves will always produce a “sharp” edge in the final render. This is due to the fact that semi-occluded pixels cannot be composited “over” the geometry render.

This tutorial explains why holdout meshes appear to have sharp edges and how compositing and cutouts work:
thinkboxsoftware.com/kmy-com … nd-mattes/

The tutorial is for Krakatoa Maya, but the exact same thing is done in Krakatoa SR, if you enable “occluded” particles in the render, and specify a file name in your output files. The function is:
void krakatoa_renderer::enable_occluded_rgba_render( bool enable );
and providing a filename in the file_saver class if you’re using it.

But again, the edges will appear sharp in the Krakatoa render until you composite with the background particles.