Animation prepass only renders last image of animation instead of "prepass image"

[silverwingsltd]

Hi

I'm going nuts here, trying to render out a prepass for animation. Instead of getting the blurred out "prepass image" vray renders out the final frame of the animation..?
I have ticked the render out the active time segment (nth set to 1)
ticked off Don't render final image in global switches
Ticked on use camera path in both IR and LC as well as don't delete and autosave
modes have been set to animation prepass and fly through (have also tried out other combos but no luck)

What am I missing?

I also noticed that when hitting the vray render button (in the vray toolbar) vray only renders out 1 image and when starting the render from 3ds max render setup, it renders out all the images?

[silverwingsltd]

Ok
I think I have narrowed it down to either the camera or the time segment. Opened a model where the prepass settings worked, made a copy of the camera (that worked with the settings) moved it to a new location and made a new key path and hit render...
but no prepass image... Again... somebody?

I'm working with vray 3.6 and 3ds max 2018

[tashko.zashev]

Hi,

Are you using the Path constraint controller for this camera movement? We have found an issue recently with this setup and use camera path option.
If not, then please post or send your scene for a further investigation to support@chaosgroup.com

[silverwingsltd]

I've only moved the camera target to make a circular movement to look around in a room. I'll gladly send the scene..

[tashko.zashev]

We just received the wetransfer link. Thank you.

[silverwingsltd]

Cool! hope you guys can figure it out

[tashko.zashev]

I also noticed that when hitting the vray render button (in the vray toolbar) vray only renders out 1 image and when starting the render from 3ds max render setup, it renders out all the images?

The render button from the VFB toolbar will repeat only the last render, in order to render production/animation you need to use the render button from the 3DS Max main toolbar.

As for the use camera path option, it's important to have some camera movement to get GI samples for the entire animation. Animating the camera target only doesn't force V-Ray to cover the entire animation time line for GI calculation. What you can do in this situations is to add keys for the camera itself by adding a very small movement. It's important to have those keys added at the same frame position used for the camera target animation.
Additionally you don't need to use Fly-trough mode for the Light cache when Use camera path is enabled. Both options are identical and its recommended to use only one of them.
After making those changes in the scene you will see a blurry GI prepasses (the last animation frames is mostly visible during this calculations) then at the rendering stage the first frame will be processed.


You may run into the issue reported here https://forums.chaosgroup.com/forum/...rking-vray-adv
So you can use the Brute force/ Light cache combo instead until we manage to fix the insufficient GI samples with "Use camera path" enabled