Cineversity

Hi gang.  I’m hoping one of you can help me solve an issue I’m having with emitters.  I’m attempting to emit sphere particles through an emitter that burst up through a hole that is just slightly larger than the spheres.  When I do so, I experience 2 issues.  First, some of the spheres are intersecting with the nearby geometry.  Second, I can’t seem to control the spheres; they shoot out of the hole in random directions with random speeds.  I’ve played extensively with the emitter and can’t find a solution.  I have both a 7 MB Cinema 4D file and a 123 MB After Effects movie illustrating the issue.  I would like to include them, but am limited by the attachment size below.  Thanks for your help!

Mark

Hi Mark,

I have send you an upload link for the file. (Private Messages: CV)

Please reduced to the emitter and the spheres. Nothing else, thanks.

I will have a look into it.

All the best

Here is your file back, Mark.

Thanks for uploading it.

I have no idea if they should fall back or just emit. If no “Gravity” is needed for the particles, switch it off or delete it.  The Acceleration Speed is the key parameter here.

The parameters you might adjust are the Emitter Size, it should be 0 in both cases, as well the Angle should be left at 0º, if a straight path out of the hole(s) is wanted.

The Selection Objects “DY” and “EM” are there to make adjustments faster, restore selection to access all five each time.

If the Dynamic Tags are selected:

Attribute Manager>Force>Follow Position

… is the next parameter to adjust. Which plays in conjunction with the speed of the particles.

In the same selection (“DY”), you might check the Mass in the Dynamic Tag, if gravity is a wanted part in the set up.

All the best

Scene file
https://www.amazon.com/clouddrive/share/U6NCgI1kZRvkqz7YLGpN6sH8ZhrGHxy6ktbennNWzjS?ref_=cd_ph_share_link_copy

You solved the problem for me, Doc.  Thank you!  Turning the emitter size down to zero, then playing around with the speed did the trick.  I was under the impression that the emitter size needs to be larger than the objects it is emitting. 

On another note, do you have any quick solutions for fixing flicker in an animation?  I’m using the Physical render with no GI and I seem to be getting small amounts of flicker in textures such as grass and stone.  I’m using a Subdivision Sampling value of 4.

Thank you so much for your help!

You’re welcome, Mark!

Thanks for the nice feedback.

The Rendering issue. Take the Interactive Render Region (Option/Alt + R) to define the area with the least quality. As small as possible.
Then use inside of the Render Settings> Output>Render Region and enable it as well press the “Copy from IRR” button.
Limit your time frame to the “sequence” with the most trouble.
Now your rendering should be very quick, and allows for an fast evaluation of the settings.

The value 4 is considered medium quality, but that is always a relative term, as each scene is different.

A nice way to get good results is given in this series by Patrick Goski.
https://www.cineversity.com/vidplaylist/the_physical_renderer/the_physical_renderer_-_part_1
Each scene has its own little sweet-spot, and I guess to find this sweet-spot, patrick’s series is a great support.

All the best

Thanks, Doc!  I have a feeling this render is going to take days.  Might be time to look seriously at either Octane or using a render farm.

A render farm is certainly a good idea to use all available resources.
How far any of the nearly dozen 3rd party render option comes close to your idea of quality is certainly a tough question.
I hope you can test ride any of these long enough to have the tool you need.
My best wishes.