Author Topic: Object-Masks in Multipass  (Read 145 times)

2019-02-10, 23:21:34

Vizoom

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Hello,

Many of us render object-masks, which are absolutely essential for all the post-work!
I find the best way is to use the monochromatic black&white mask for every object-group of same materials and I´m happy that Corona-C4D offers this feature in its multipass (...with Object-ID or Material-ID).

But I really miss two things...or perhaps I just don´t know how to adjust it(?)

1.
Masks for objects behind glass!...It´s very often the case that in an exterior we have also  to tune objects inside the building, columns, stairs, furniture, people etc...but Coronas masks dont take into account that there are transparent objects in the scene (glass in windosws e.g.) and corona doesn´t generate masks for any objects behind glass...
In native C4D it worked well: The masks for all transparent objects are defined otherwise then masks for opaque objects (transparent objects appear in the masks with different shades of gray depending on their transparency) ... and we get also object-masks for all objects behind the glass ....
It seams that in coronas masks glass is seen as every other object....
So currently the only workflow to get all masks, also for objects behind glass, is to change the scene after rendering to native C4d, throw away all lights, change the material of all transparent objects to native C4d-material with transparency....and render this scene again with C4d native renderer to get the right set of object-masks...
Sometimes a little tricky because of corona-materials with alpha and of course an additional work every time!

I just spoke to another person from another studio....they have the same problem and their workflow it exactly the same I described with a second render;)....

2
When saving to a PSD-file from native C4D, all object-masks are automatically inserted in PSD-channels!..it´s great, because when you need a selection, you go to the channels, cmd-click (on a Mac) on a channel icon and you have your object selected....
When saving to PSD after a corona render, all the objects masks appear as layers, not as channels :(.....Would it be possible to cahnge it or to have the choice ;)))!

Thank you very much!!!
« Last Edit: 2019-02-10, 23:37:54 by Vizoom »
vizoom | visual craftmanship | berlin - barcelona

2019-02-11, 09:42:43
Reply #1

James Vella

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1.
Masks for objects behind glass!...It´s very often the case that in an exterior we have also  to tune objects inside the building, columns, stairs, furniture, people etc...but Coronas masks dont take into account that there are transparent objects in the scene (glass in windosws e.g.) and corona doesn´t generate masks for any objects behind glass...
In native C4D it worked well: The masks for all transparent objects are defined otherwise then masks for opaque objects (transparent objects appear in the masks with different shades of gray depending on their transparency) ... and we get also object-masks for all objects behind the glass ....
It seams that in coronas masks glass is seen as every other object....
So currently the only workflow to get all masks, also for objects behind glass, is to change the scene after rendering to native C4d, throw away all lights, change the material of all transparent objects to native C4d-material with transparency....and render this scene again with C4d native renderer to get the right set of object-masks...
Sometimes a little tricky because of corona-materials with alpha and of course an additional work every time!

Im not a C4D User, but check under the Advanced tab for your Corona material and see if you have this option (attached). Uncheck on your glass material "Visible in masks".

2019-02-11, 11:14:32
Reply #2

HFPatzi

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+1 for the second Request from my side!

2019-02-11, 17:50:38
Reply #3

Vizoom

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Im not a C4D User, but check under the Advanced tab for your Corona material and see if you have this option (attached). Uncheck on your glass material "Visible in masks".


Thanks!..I will check it...but this way I sacrify a mask for glass to get the masks for objects inside?...right?
vizoom | visual craftmanship | berlin - barcelona

2019-02-11, 18:50:10
Reply #4

James Vella

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Thanks!..I will check it...but this way I sacrify a mask for glass to get the masks for objects inside?...right?

Correct, However I use the refraction pass as a channel for glass masks.

2019-02-12, 22:59:37
Reply #5

Vizoom

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Correct, However I use the refraction pass as a channel for glass masks.

Oh, yes, this way it should work..:)....Thanks!
vizoom | visual craftmanship | berlin - barcelona