Motion Blur Render Time Increase

[J_Bug]

Hi all,
I've created a short 45 frame animation of a car driving down a city street. The car, two of it's wheels and the camera are all animated. Should MB increase a 5 min per frame rendering to 1.5+ hrs per frame?

Any suggestions on alternatives to VRay MB? Or tips on settings? I cut the min/ max samples in half with an obvious loss of quality but it didn't really decrease the render time that much. I've also switched to Analytical MB but my reflection bounces looked like they were lowered by this

Thanks,
--Jon

[cpnichols]

for high poly scenes try using Monte Carlo MB rather than Analytical MB. If all else fails you can do a simple 2D motion blur with straight MAX... will not look as good but you can at least try it. Use the Motion Blur, Effect in MAX... it will render in Vray as a post effect.

[Biohazard]

If you don't care to gain *real life* MB, use a 2D MB coming from any compositing or editing package (such as AFX for exemple). Sometime, it's just worth the sacrifice.

[J_Bug]

Thanks guys, I wasn't aware that the 2D MB effect worked. Good to know now I was considering using AFX but I think I'll try the render effect first.

Thanks again,
--Jon

[vlado]

Re: Motion Blur Render Time Increase

I've created a short 45 frame animation of a car driving down a city street. The car, two of it's wheels and the camera are all animated. Should MB increase a 5 min per frame rendering to 1.5+ hrs per frame?

If you render individual frames, do they show the same render times as when rendered in sequence?

Speed of rendering with motion blur depends on how the objects or the camera are moving. Faster moving objects take more time. So if your car accelerates, then it's normal to have increased render times.

Best regards,
Vlado

[Biohazard]

oups, forgot to mention the name "real smart mb"...

[Christian]

did anybody use MB and DOF togehter?

I don´t think that using 2D mb is the way to go. There are too many mistakes and vray´s mb looks really fine.

The rendertimes increases so much when you use MB and DOF together.
If you only use one of them the renderiing time is acceptable but together it increases to more than twice of before.

I hope Vlado can find way to make it much faster. Rendertimes about 2h are uncool.

Greetings
Christian

[J_Bug]

Vlado:
The render time increases as the car approaches the camera but this happens even if I'm not using MB. Without MB I go from around 5 min to 12 min per frame. I think it may have something to do with the fact that the camera is panning into a brighter area of the scene.
I'm curious to find out if you still plan on implementing selective motion blur. If so would we be able to maybe select say the tires and the car for true 3D MB then apply the render effect to the rest of the scene?

I should probably consider learning to comp better in AFX so I can just do this manually but it's always nice to be able to do it all in MAX for short little demo pieces like I'm trying to create for a reel.

Biohazard:
Is "real smart mb" a plugin for AFX? Haven’t touched AFX in about a year or so but I like it and hope to get back into it soon.

Christian:
I think VRay MB looks excellent also. I want to put it on everything but a jump from 5-12 min all the way up to 1.5hr is a little extreme for me. I still have to model more key objects for this scene I'm working on in my spare time. I'll probably try to apply it to a little more tame scene that I've been wanting to rerender in VRay.

Thanks
--Jon

[Moose]

J-Bug, some info on ReelSmart Motion Blur plug

[J_Bug]

Thanks Moose