After Effects CS6 Tutorial - 85 - Quick Guide for Track Mattes Part 1 Video Lecture | Adobe After Effects CS6: Complete Course from Novice to Pro - IT & Software

hello everybody welcome to and After
Effects cs6 tutorial
I'm your host buddy Blackford and today
I'm going to teach you the basics of
track mats and Alpha's so there's an
alpha mat and a luma matte when you're
working with track mats and I want to
show you quickly how to get to track
mats here so down here at the bottom
there's a toggle switches and modes
button and click on that to get to this
section here where it says TR que ma T
that's your track mat so a track mat
will enable you to take the alpha or the
luma of your image or text or whatever
you have that has an alpha on it or
luminosity on it and it will allow you
to take what's underneath it and apply
it onto that layer so for example I
could take I could show you right now
that this text right here
has an alpha on it by going to this 3
red green blue circles here click on it
then come down to alpha and anything
that's in an alpha that is white is
going to end up being transparent and
everything that is black is just going
to be cut out so anything underneath
this layer which is going to be my
background layer it's going to pop
through on the white and not on the
black so I will put it back on to the
RGB here so we can see I'm gonna enable
my layer again and I'm gonna show you
how the Apple works on this color does
not matter when you're working with text
with an alpha so I'm gonna come down to
this button to this drop down menu here
and make sure that your text is on top
of your background
I'm gonna come down to alpha Matt and
we're gonna see that the what the Alpha
they're picked up what was underneath it
which was the background layer and and
everything else was cut out
that's called a mat it's kind of like
masking out things using the Alpha of
the object now if I just wanted to use
that text to cut out of the background I
would just come down to here and go to
alpha inverted mat and you could see
that the text is cut out if I come down
to my transparency grid button here and
click on it you can see that the Alpha
is indeed cutting out of the background
so that's how you cut things out it's
kind of like the subtract of a mask so
there's alpha mat which is like an ant
on your mask or the Alpha inverted mat
which is the subtract now I want to go
over luma mattes with you I'm gonna put
this on no track mat again and enable
the eye here because once you enable a
track mat for something above it it it
turns off the eye there it turns off its
visibility and a luma matte basis the
mat track mat on the luminosity of the
object meaning how close it is to black
and how close it is to white kind of
like how bright or dark it is so the way
I'm going to show you that is I'm gonna
add this four color gradient onto the
text I'm gonna click on the effect and
here we have black over here on the Left
which is dark which means that's not
gonna show up when we try to use our
luma matte and over here is more white
that's going to show up even more when
we use our luma matte so I'll show you
real quick let's change this to luma
matte
and now you can see here that everything
that was black doesn't show up and as it
gets closer to white it's now showing up
even more let's change the opposite
invert luma inverted matte now it's just
cutting out but the white part is
cutting out more than the black part so
when you have something that's darker
it's not gonna be affected as much by
luma mat when it's whiter it's gonna be
affected by the alumina luma matte even
less or even more I'm sorry even more
when it's white now if I come down to
here and check out my alpha of this with
the four color gradient on it it's still
the same so the luma and the alpha are
completely different things they just
used the same kind of color values on
here that the they just use the black
and white color values to demonstrate
what's going on and use what's getting
cut out or what's getting faded out or
what's getting replaced etc