Speed up render time for complex scene

[Anonymous]

Hey guys, 

I have a pretty complex scene and am getting closer to start rendering.

Its an animation of about 2 minutes length and the only thing animated is the camera. Everything else is like a snapshot in time.

Right now it takes me already about 2mins to render a single frame and it will become even more once I have placed all my characters and objects. And just to render a 2 minute animation, where every single frame takes about 5 minutes(I hope it doesn't get even longer like in my older animations, so it's already quite optimized) will take me up to 10 days to finish. Well, the problem is, I don't have 10 days for that anymore(I will probably need to reduce the resolution to make it).


My question is, since only the camera is animated and drives through the scene, is it possibly to somehow save all kind of light interactions(I am using an HDRI environment) in a cache file, so that that doesn't have to be calculated every frame? 
Also what else can I do to get rendering faster? (I am rendering with Mental Ray)

[maciejwypych · Accepted solution]

Hi,
In the Global Illumination settings, go to FG and select Project FG Points From positions Along Camera Path.

You'll need to play with the settings depending on the camera speed, quality, etc....

In the Global Illumination settings, go to Reuse (FG and GI Disk Caching) > Final Gather Map
And select - Incrementally Add Fg.....
Select a file to save the FG.

Select -

Render

After it will finish, deselect the Calculate FG/GI and skip final rendering and change the setting to Read from file.

Check out these tutorials - http://www.3dtotal.com/index_tutorial_detailed.php?id=1500
http://www.ronenbekerman.com/making-of-the-house-3d-mental-ray-animation/

And help
http://docs.autodesk.com/3DSMAX/15/ENU/3ds-Max-Help/index.html?url=files/GUID-E6A86C2D-19C5-46C7-9DA...

[Anonymous]

Thank you very much, I will try that out!