VRayObjectSelect

[Syclone1]

So Im trying to use the VRayObjectSelect Element to render 3 objects in my scene using (G-Buffer)Object ID# and in the VFB for each one shows just the separate objects but when I try to save each one the saved image file shows all 3 objects together and not just a single one that was selected or showing in the VFB. Is there a bug or user error?

[Zdravko.Keremidchiev]

I can't reproduce this behavior with a simple scene. Which V-Ray version is this and can you attach an example scene?

[Syclone1]

Sure Ill put together a file shortly, using 3dsmax 2016 SP3, V-Ray 3.50.04

[Laserschwert]

And regarding VRayObjectSelect, can I get that element's Alpha channel (which is different from the main pass's Alpha) only when outputting to EXR?

[Syclone1]

OK here is a simplified scene and 1 of 3 elements in it from the vfb. I cant attach a max file so Ill shoot it to support with this thread linked.

*nuked the attachement as it was a PNG and it got converted on upload to a jpg* Ill attach it to the same email as well

ticket number is: #670011

Ok just for S&G here are 2 element channels from the simplified file showing what I see and what I was expecting is that I would get each ObjID alone with nothing else but I get an alpha of the other objects with it which is useless for compositing that back in to PS as some of the objects are very complex.

[dans]

AFAIK:
The V-ray VFB never shows render element specific alpha channels, but they can be saved - this is a known limitation of the Framebuffer I believe.
Element Alpha works correctly for VRayMtlSelect elements (I tried saving using EXR, PNG from V-Ray Framebuffer and PSD using psd-manager)

When using VRayObjectSelect there is no element specific alpha channel (I used 3.50.04, 3ds max 2017). Alpha looks just like the Beauty alpha. The RGB channels were correct in my tests. The documentation claims transparency support, I'm not sure of this ever worked.

Daniel

[Syclone1]

I got the following from Support this am:

This is limitation on VRayObjectSelect Element.
VRayObjectSelect Element do not have own alpha so when you save it in format that supports alpha channel the saved Аlpha is for the RGB color Cannel.

Similar to you desire result you can achieve if you use MultiMatteElement
with which help you can extract masks to remove any unwanted data in your compositing software.