Mask Script

[glorybound]

Any mask scripts that work in MAX 2019 and the newest VRay NEXT? The last four I tried all failed.

[Morne]

What do you want to mask?

[glorybound]

I am working with GPU and the VRayObject ID doesn't work. I need to mask out some glass.

[Morne]

Just tried it with a multimatte and it works fine in both setting it as material id or object id
it also works fine in multi channel exr as well as split channel

....using GPU

[glorybound]

Doesn't work here. I get a filtering warning and I am not sure if that has anything to do with it. I pick my glass and I give it an object id. When I pull down the VFB it'll show, but when I open the EXR in PS it is black. I learned my lesson before so I save the element as a jpg, but I forgot on one still.

[Morne]

ok, but are you using a multimatte render element?
also in PS do you have the latest EXR-IO plugin to read the multichannel EXR?

[glorybound]

I used the VRayObject ID. I'll try the Multimatte render element

[glorybound]

I used multimatte, but it's lame that you can't use a PS selection tool in 32 bit.

[Morne]

I used multimatte, but it's lame that you can't use a PS selection tool in 32 bit.

With multimatte, you use the entire red or green or blue channel as the "selection"

Typically if your id was 1, then you use the red channel of the multimate as the mask. Stick on an adustment layer, exposure for example, then use the red multimatte channel as a mask on the exposure. Then you can adjust only the brightness of the exterior. If you plan on replacing the background (or stuff behind the glass), remember to override black environment refraction

Instead of the exposure, you can make a group and inside the group stick your reflection, refraction and specular render elements. Then on the entire group you can stick the mask and set the group layer blend mode to subtract, then you can stick other stuff in as the background and later add the layers back in again (without refraction, because replacing the background, you're essentially replacing your refraction - well, in a nutshell)

32bit is a very powerful and flexible way if working when you understand the math behind using render elements

[glorybound]

I'll have to work through it. I just want to pick , let's say red, but in 32 bit I can't. I have to copy it out, change it to 8bit and select the red, and paste it back in. Your description makes sense.

[Ihno]

If you want a selection from a Multimatte layer you can do the following:
Make sure you have the Multimatte Layer enabled and on top, so you can only see the Mm layer.
Now go to channels and ctrl+kick on the channel you want a selection from.
It works in any bit depth.

[fixeighted]

Why not this? Seems to do all you need
https://www.exr-io.com/