Material ID

[Danielhruby]

I have added an Additional Output item int he shader tree at the top along with the Alpha output and finally color output. I enabled the Material ID so that I could use it to tweak in photoshop. But it renders solid black. is there something else I need to do?

[John_Do]

Hey Daniel,

Yes, one more step : add a V-ray Properties package to your material group, and specify it color for the Material ID pass. See the how-to in attachment ( you have to click on it to be displayed properly )

Material ID is very convenient but if you're not allergic to render elements I suggest you to use the Multimatte render element. You may need several Multimatte elements to get all your materials masked, but the mask attribution and creation process is automated thanks to Vladimir, so fast. Last but no least, you'll get perfect masking because the masks use RGB channels that you can easily transfer in alpha / mask channel, without crappy aliased magic wand selection.

[vladimir.nedev]

Also, unless you have the new 3.7 nightly build, you have to specify a non-zero multi-matte ID or the material ID color won't get picked up.
This is fixed in the 3.7 builds.

Greetings,
Vladimir Nedev