Motion blur killing scene Tweet

[ajiblock]

Windows 10
x2 GTX 1080 Ti, x1 GTX 1070
64 GB RAM
On the latest for the 10 series drivers, 430.39
Octane Version V.02.1-R3
Cinema 4D R17.055

Hi,

I'm having a weird issue with motion blur on the C4D Octane Camera tag that is stopping me from being able to finish a project.

I've been working on this shot for a few weeks, rendering it as I'd expect with Motion blur. I hadn't really changed much and I started to notice in live viewer that the motion blur was not rendering the way it'd been working previously. I know motion blur isn't always 100% accurate in live viewer so I did a lot of render tests to picture viewer, etc. I've attached a folder with screenshots of what is happening.

I've tried to debug the file item by item but can't figure out what is wrong with it. In the folder I've included a previous iteration of the file (V1) where the motion blur works correctly, its close to identical except there are some keyframes on the camera, positions of things etc that are different. The V2 is the one I need to work but when I turn on motion blur weird things start to happen.

I tried to attach the file but it's a little big so I think it timed out, here's a wetransfer, hope that's ok – https://we.tl/t-n2UqiXeEIz (if not I can reattach without the high res texture maps, but just wanted to give you exactly what I had as I'm not sure what causing the issues)

[aoktar]

Don't know what's weird here but what I see in first look: Your scene is even heavy for C4D viewport. Is there any special reason to don't use render-instances for all clones? Actually only some clones are render-instanced.

separately, you can test the clones for motion blur by completely disabling the two top cloners.

[ajiblock]

There's a time offset on the step effector and when I use render instances on both cloners I think that won't work? Scene is very heavy agreed. Would've preferred to use scatter / instancing but didn't because of the time offset effects.

Are you able to render the V2 with normal motion blur? Everything is fine but that is when I run into problems. If you look at the included screenshot when I turn motion blur on in the V2 file (even with instancing enabled on both cloners) thats what I see in live viewer, it looks like its just an image of my Sky's HDR or something. When I render to picture viewer it's an incoherent blur that looks nothing like the motion blur in the other file ( despite the cameras and camera tags and files being almost identical)

edit: after testing more with instancing on for both cloners I think the motion blur tag is somehow changing the composition or trajectory of the camera, which is why I see nothing in live viewer except the sky HDR. Is that possible, and is there a fix ?