Blackmagic Forum

hey there,

im trying to apply some motion blur to the 3d particles in fusion.
usually i get lucky with trial and error but cant seem to get any results here.

i am demoing reelsmart motion blur also with 0 luck.

can anyone give me some pointers please. my searches were not successful.

thanks,

d

You need to make sure that motion blur is turned on (click the yellow "radiation warning" icon and check as necessary) in both the particle render node and the 3D render node and that the settings are exactly the same in both locations. Otherwise it doesn't render.

thank you very much for the reply JP

the nuke was apparently replaced by a nondescript circle symbol in f8
i am getting something but it looks more like traces of particles more than blurring.
probably need some tweaking.

so since i have mblur on both 3d and pRender, which one should i use to control the blur?

As per my previous note "both settings have to be exactly the same" so you need to control it by setting both nodes motion blur settings to exactly the same thing.

Quirky, I know, probably that way because I believe the particle system predates the current full 3D system by a fair long way . . .

And yes it will take a fair bit of by eye tweaking and possibly beefing up in the 2D comp to get it to look right. Bear in mind that basic particles are points with no real size, so motion blur is iffy at best. For motion blur it's often better to use the blob sprite and tweak the size and colour to taste.

There's some good particle stuff here

http://www.steakunderwater.com/VFXPedia ... Simulation

mostly by Gregory Chalenko who is a real wizard with the fusion particle system.

And here

http://www.steakunderwater.com/VFXPedia ... le_Systems

a lot of the links are broken and they are mostly on old versions of fusion but some of them still work, as the particle system hasn't changed for yonks.

thanks jp,

sorry i missed that settings comment.

i already am using the blob at this stage, but im not sure if i can get what i´m after with the native particle solution. if the particle system hadn´t been changed for that long, i suppose there have to be better third party alternatives. i will definitely look into those links aswell.

appreciate your help, thanks again.

To have a good motion blur you need also to increase the sub frame steps in the pRender node. So, the particle steps between the frames are calculated. This will change the look of your particle simulation and it can take some time to calculate but AFAIK it's necessary to get the right blur

thanks michael,

this option helps aswell but im getting some strange behaviour with blob. as if the alpha of the blog is not registered. i´ve attached a screencap. ngons seem to give me more interesting results.

on the whole, the particle system seems a bit basic. i dont see a way to import a use a custom mesh as a particle but i presume there has to be a workaround.

i also would like to have particles interact with light, as if dust specs would if seen under certain angles.
is this viable? can particles have material properties.

im jumping way ahead of myself, i´m working on a project and would like to use fusion as much as possible and i have no idea what its limitations are.

Hi Denis.

I believe that you problem with the particles' alpha can be solved by changing the transparency setting inside the renderer 3D from "Z-Buffer (fast)" to "Sorted (accurate)"

In the viewers this can be achieved toggling the button "FAST" in the bottom, but it does not affect the render.

All of the particles are either points, lines, or quads. They can have materials assigned to them, but you might not have the interpolants set the way you need. You can use Replicate3D to instance geometry to the particles. Particles can be used to make volumes for VolumeFog if you want certain soft lighting effects.

thank you both for the replies.

@chad, i was not referring to volumetric scattering or light shafts. i´d like to have larger particle flecks that only become visible once the travel through direct light -same as dust particles do. since materials can be used, i suppose that will work.

since you mentioned volumes, does that mean that fusion has a path tracing engine?

Denis Mujakovic wrote:since you mentioned volumes, does that mean that fusion has a path tracing engine?

Raymarcher.