If I render with Krakatoa Motion Blur, the additional (blur) renderings seem not to take into account the Matte Objects. Has anyone ever experienced a similar issue or am I maybe just missing something?
I tested out the matte objects, and I wasn’t able to reproduce what you describe. Maybe I am not setting my scene up the same way.
About your scene:
Is your matte object moving? Do your particles have velocity?
Can you describe in a little more detail what you are seeing? Or possibly provide a scene for me to try rendering?
I also have the problem with animated matte objects not matching with the rendered particles when motion blur is activated and ‘Particle Segments’ is set to a higher value than 2. The particle motion interpolation is correct, but the matte object moves much to fast.
In my scene I have an fast moving animated mesh (geo cache), and it seems as if the matte object would not be interpolated in frame sub steps but in whole frames only. So with 12 particle segments the particles only move the desired distance (as seen in the viewport), but the matte object produces an hold-out of about 6 frames before and ahead - which is unusable.
As a workaround, I reduced the shutter angle to about a sixth or a tenth of the value (so that the movement of the holdout is correct) and then applied a scale channel modifier to the PRT Loader and multiplied that factor to the velocity. It did work for me in this particular scene, but produces not exactly the same result as if the motionblur would have been the correct shutter angle values.
Would you please check this problem? My Version of Krakatoa MY is 2.2.0.51871…
I think I have an idea of why this is happening.
How Krakatoa works:
-Krakatoa uses multi-pass motion blur.
-Velocities are generated for each vertex in the matte mesh.
-When a Krakatoa motion blur pass is rendered, the mesh is offset to the desired shutter time based on these vertex velocities.
How we get vertex velocities:
-We sample the mesh at the current time, and at time +0.5 frames to generate the vertex velocities.
So if the mesh is not animated smoothly in the subframes, then Krakatoa motion blur will not look correct. That’s what I think is happening in this case.
I would like to solve this problem. I hope you can help me do so.
-Can you provide me with instructions to set up a scene that produces these meshes (I assume I will need to produce a geo-cache).
-Or, better yet, can you provide me with a simple scene that shows the problem.
With a sample scene, I should be able to solve the problem, and send you a fixed build.
sure, I have prepared a scene. You can see in there that the matte object moves faster (or let’s say an other range) than the particles. So the cutout does not fit…
Because of the particle-cache files size the scene-archive will be too big to post, can i upload the scene somewhere?
If you zip up all the required files, are they under 512mb?
If it’s under 512mb, you can upload it via our support form here:
support.thinkboxsoftware.com/open.php