PDA

View Full Version : Matting mr mblurred objects with FumeFX (scanline)

Glacierise
06-15-2008, 09:22 AM
Hi guys, I have a problem here I can't figure out. I render my geometry with mental ray, and the fumefx/afterburn effects in scanline. The problem is when I need the geometry motion blurred - i.e. almost all the time :D Mr and scanline compute motion blur differently, so the mattes and geometry don't fit. One solution is to use image-based motion blur (reelsmart) on the whole sequence afterwards. Is there another one, like some kind of mblur that computes the same on both renderers (i doubt it)? I desperately need an answer to this one.

Thanks!
SoLiTuDe
06-15-2008, 10:53 PM
Yeah, it's a bitch dude... never gonna line up perfectly. Good thing to do for starters if the camera is moving is to create a giant sphere around the scene, invert the normals, apply a matte shadow to it, and render... you'll get some moblur on the fume stuff itself this way, and your matte lines shouldn't be as bad. Otherwise you'll have to grid-warp the stuff (depending on the program) which means just warping the fume layer to line up better. Not fun. :D

Edit: oh yeah -- there's also the image motionblur render effect (as opposed to in the render dialog) and that will make the object have the same motionblur.... still suggest doing the sphere thing though as well as this.
Glacierise
06-16-2008, 11:56 AM
Damn even you guys haven't solved that! The grid warping thing, that idea seemed scary. And demanding a few slave laborers :D I'll try the sphere trick, and the image based mblur. It would be cool if mr gets atmospherics support, but I wouldn't bet on it. Well, that's life :D Thanks for your expert advice Solitude, always appreciated!
SoLiTuDe
06-18-2008, 05:27 AM
Yeah, it's either gridwarp or rerender, and sometimes (usually) it's quicker to gridwarp it. Dirty workaround, but it works. :shrug:
CGTalk Moderation
06-18-2008, 05:27 AM
This thread has been automatically closed as it remained inactive for 12 months. If you wish to continue the discussion, please create a new thread in the appropriate forum.