separate channels in nuke (multimatteelement)

#1

Hi
I have a rendered a car and a multimatteelement pass , the rims are green, body is yellow, glass is red. my question is, how can i isolate the rims? if i shuffle out my green channel, the body of the car appears too because the yellow uses the green channel too right?
Is this clear? :slight_smile:
Thanks in advance

#2

best way is to render only primary colors in a matteelement (RGB), this is the only way to get clean and nice mask out of it
all other methds tend do give you edges and fringes

but in your case you can substract the red from the green, which should let left only the parts that are only green

or you could try to use a keyer on the mask, instead of a shuffle

or look at nukepedia for some gizmo which makes the mask seperation for you

#3

Hi
Thanks for your fast reply.
Yes, i usualy render out a multimatte only with the primary colors, but for some reason they were mixed :slight_smile:
i tried the shuffle way and worked nice. :thumbsup:
going to check nukepedia and the settings of the multimatte.
Thanks a lot :thumbsup: