Ignore opacity for MultiMatte element

[peprgb]

Is there a way so that i can get myr red (g o blue) matte rende relement ignoring the opacity of a material? while it's not ignored in beauty pass of course.

I have a perforated steel sheet and want to slect all, not excluding the holes, for post production.

Here the images, so i want the red ignore opacity so i can select all the shape...



If not automated way i will assign a VrayLight and isolate the building...

[peprgb]

Mmm no light here?

I found the way of isolating the building and applying VrayLightMtl, also with Matte ON and Alpha cont. -1, or VrayObjectID (but needs to be Integer, no AA)....i guess must be a faster/better way to do this

[svetlozar.draganov]

You can try with VrayMtlID / VrayObjectID / RenderID - Render Elements- they ignore the opacity of the material !

[peprgb]

Thanks!! VrayMtlID is the good one for me.

_ RenderID separates lots of pieces (image 2)
_ VrayObjectID works fine, ignoring the opacity, when set to "Integer (no AA)" (image 3), but not at all when using "Color (with AA)" (image 4), and AA is a must so...

EDIT: Image 4, Color With AA, seems to ignore opacity but not reflections, since the vertical dot stripes are glass sheets behind the perforated sheets....