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Hello people,

Never had to use the motion vector pass before this job as I was just using the beauty with the motion blur baked in it, and after spending few hours on the web, i'm hitting a wall.

Octane produces an image with roughly blue to orange colors. As I understand it, it produce positive and negative values. It doesn't work out of the box with RSMB pro vector.

Anybody with a workflow to make it work? What am I doing wrong?


**** My workflow *****

In c4d/Octane :
Activate the motion blur in the camera tag.
Set my shutter speed.
Activate my vector motion pass.
Result : my blue to orange image more or less intense depending on the speed of the camera move.


in after effect :

import my beauty pass
import my vector motion pass
add rsmb pro to my beauty pass
link my vector motion pass in rsmb

Result : everything is blurry, not how it suppose to be

Hi,
have you already seen this tutorial?
https://vimeo.com/33243611
[vimeo]http://www.vimeo.com/33243611[/vimeo]
ciao beppe

Hi,

Thank you for the link.

Yes I did. But if im not mistaking, he is using c4d render motion pass, not octane. Which work pretty fine (which I also rendered for my project).
As I said, I'm really curious to understand how to use the motion vector pass from octane with rsmb. If it is even possible.
Or at least to understand how it is intended to be use.

I hope it makes sense!

Thank you!

Also want to know how to use motion vector pass from octane inside AE

Did you check the "preserve RGB data" box in the "interpret footage - color management" menu? This is namely what the video is focused on.

Hello,

So I made a video, with a very simple set up, just so We are all seeing the same thing. Unfortunately, I don't think it has anything to do with the preserve RGB - I checked.

https://youtu.be/NS3_9M5DRc8

Top Left : result from octane, I exaggerated the blur so we can see the effect, it looks great - but let's say I need it to be control in post so I won't be able to use it.
Top Right : The result from Octane pass, which vary a little different from the LV (grey background color, probably a gamma/ situation - I'm not entirely sure)
from the Picture Viewer = from the live viewer LV = As you can see, it produces the full spectrum of colors. It is coded also but not sure how to use it with rsmb in ae.

Bot Left : The world pass from C4D - Just because I wanted to compare it to the Motion Vector pass from Octane as it looked similar. Not relevant obviously.
Bot Right : The vector pass from C4D - which produces color coded values that RSMB understands. (green, and orange, not blue cf. help from c4d)

Let me know what you guys think.

Have a good week end!

LV use tonemapped buffers. Render settings passes have a parameter for switching between linear and tonemapped. Did not ever notified?

Thank you for the clarification Aoktar, I could feel this has to do with this tone-mapped buffer. I never had to change those settings before as I stayed linear. Thanks again though.

Regarding the use of the pass itself, do you know by any chance how to use it?

mrpinoux wrote:Thank you for the clarification Aoktar, I could feel this has to do with this tone-mapped buffer. I never had to change those settings before as I stayed linear. Thanks again though.

Regarding the use of the pass itself, do you know by any chance how to use it?

You should not use tonemapped colors on passes for correct results. I don't use any effect in AE and also i never preferred to use passes in my jobs.
But it's like that for velocity vectors:
xyz->rgb values.
x->red, y->green, z->blue.