First time user here, so please bear with me if i am missing something obvious.
The manual says zdepth is calculated from the nearest particle to the farthest.
This makes no sense. If zdepth is figured this way it will be different for every frame. Moreover, this makes it incompatible with compositing, as standard 3d renders are calculated with a zdepth pass that is based either on distance between camera clipping planes or an arbitrary range set by a shader.
A depth of field calculation in a compositing program will not match between particles and geometry, and would flicker every frame of the particles.
Please advise, and thanks in advance.
T
I believe it just means that the nearest particle paints the pixel. It does not mean that the value of the pixel is normalized from the nearest to the farthest.
An asside, Zdepth isn’t very useful in compositing krakatoa unless you have only super dense renders. What is the z-depth of a wispy cloud?
Thanks, that helps.
In this particular case (no pun intended) I need something that feels like talcum powder. It will have a strong depth of field in comp that needs to match the geo renders. Is it possible to make a pass within the existing render that uses a maya shader to map a projected ramp for zdepth? I am trying not to have to do a separate render just for depth.
Personally I would recommend doing all depth of field in krakatoa render. You’ll have to wait for deep compositing output support if you want something that behaves like a zbuffer on non-opaque objects.
benyaboy is correct, the z-depth that is generated by Krakatoa is the distance from the camera plan to the nearest particle. It is in world-units.
Doing 3d depth of field in Krakatoa would be ideal of course, but you may be able to produce something that looks good using a 2d technique using the z-depth. It wouldn’t work for very transparent particle clouds, but more solid clouds might work better.