Motion Vector Shader or Velocity render element?

[Crazy Homeless Guy]

Does anyone have experience using Motion Vector Shader in MR, or a Velocity render element? Preparing to render an animation soon, and would prefer to go 24 frames a second and apply motion blur in post. I will probably use Combustion to apply the pass, but also have the possibility of using AE.

 

Anyone, any tutorials or insight would be helpful.

[Spooner04]

I know that if you render out to a PNG you can embed the velocity pass in the file and then pull it out in combustion. I think using the 3d motion blur node. I've bought/watched some tutorials on it but haven't used it really outside of that. It will still increase your render times noticably, but not quite as much as applying the motion blur directly to the render. Other than that all the standard abilities of using it in post.

[Macer]

I've used .rpf to capture the velocity (along with the more usual channels) when rendering animations from MR. Then applied RPF Motion Blur in Combustion and been very happy with the results. Your get pretty big files, but all the info you need is contained in it and theres no messing around within combustion, it just knows that its there. (Theres a list in Combustions help files showing what rpf channels should be saved for what purposes - just search for rpf!)

 

For most of my average sized animations it didn't add any time to the rendering at all, but a recent large (5 million poly +) animation with loads of proxies couldn't make it past the loading/transforming stage of the render process:

 

http://www.cgarchitect.com/vb/34870-problems-rendering-large-mr-scene-rpf-file-type.html

 

I ended up having to abort trying to save it as .rpf's and reverted to .tif's and it rendered fine. I didn't get around to figuring out if this was an issue with the overall size, or the proxies or ??? But if I can, I always use .rpf's. As they suit my workflow - which is nice and simple!