Hair and Motion Blur not working

[lalalem]

Hello,

I made a tennis ball, which is a sphere with hair all around. Unfortunately I cannot get Motion Blur to work on it.

This is without motion blur.


This is with Motion Blur.


As you can see, all of the hair surface is not affected. Only the sphere under.

The OctaneTag (with Vertex/Transform) is on the Null, which is animated. The sphere geo is inside the null, with the hair object too.

I have tried many things : putting the OctaneTag on the geo, on the hair objet etc. Nothing works!

Any help ?

Thanks a lot

[aoktar]

1-What's your plugin version?
2-Seems like hair is blurred to me. Can't see much detailed in your low-sampled renders.

[lalalem]

1- 2021.1.1.1
2- The tennis ball is a sphere, and hair added all around the surface. On the screenshot (sorry for the low samples), it is only the sphere that is motion blurred. All the hairs have not been blurred and are floating outside.

[jayroth2020]

Your hierarchy is likely the culprit here. Please post a screen shot of your Object Manager so that we can see how you have things organized. Better yet, post your scene, or submit a ticket to [email protected]. Make sure you do a "Save Project with Assets..." archive that and send it in.

[james_conkle]

Are you using Octane scatter for the hairs? I'm pretty sure Octane scatter doesn't support motion blur but I'm sure Aoktar will correct me if I'm wrong.

Otherwise if it's with a cloner object try changing the instance type in the cloner object. Make sure the source geometry for the cloner isn't disabled (red traffic lights) and when in doubt give EVERYTHING an Octane object tag.

You also might want to change the shutter alignment to centered - I believe that acts more "realistically" in how it represents motion blur.

BTW saw this on Reddit the other day and I love the look you were able to achieve with this - beautiful colors and lighting!

[lalalem]

Thanks guys, so I think the hierarchy is not the problem because I tested loads of combinations : hair objet in the null, outside the null. Octane tag on it hair object, on geo, on both. Etc etc. Always the same...

In the end I converted all the hairs to splines, and got it to work as I need it. But this increased my render times to insame times sadly. But at least it works.

[jayroth2020]

Last week, I supported a similar issue where the hierarchy was exactly the problem. It might be in your case, it might not, but why not let us take a look and see?

[lalalem]

Of course be my guest, it would be great if you can figure it out!

Here is the file :

[jayroth2020]

Here is my test result. Your hierarchy was OK; you need an Octane Object tag on the Hair object, and the motion blur needs to be set to Transform/Vertex.

ball motion blur.mp4

(1.17 MiB) Downloaded 2045 times

[lalalem]

Well that's crazy, I was sure I tried everything. Thanks a lot, this works great!