newb question about track mattes/help with tutorial….

[Aharon Rabinowitz]

A layer that uses a track matte (The sith dude, for example) goes below the matte layer (interference).

Once below the track matte layer, you turn on the matte by telling the sith dude’s layer to use the above layer as a matte. Use the pull down to use either a luma matte (A matte based on levels of light – if you have a black and white image) and an Alpha Matte (A matte based on alpha channel). It all depends on what the layer you are using as a matte.

Anyway, the point is, if there were only 2 layers in the entire project, and you set it up so the order is:

1) matte
2) Footage to be matted

– your matte layer will not have a pull down for track matte options. That’s because a track matte is just a regular layer. What makes it a track matte is your telling another layer to use it as one.

Make sense?

Also, it’s worth mentioning, that you can use only one layer at a time as a track matte for another layer. That doesn’t mean there can only be one track matte per project. What I mean is if you stack several matte layers on top of eachother and at the bottom have the layer to be matted, then you can only use the layer immedietly above it.

So what if you want to have multiple layers working together to create a complex animated matte – the answer is take all of those layers (except the footage to be matted) and place them in another composition (this is called Called “precomping” or “precomposing”), and then nest that comp in the current comp, right above your layer to be matted).

Hope this helps.

Aharon

—————————————-
Aharon Rabinowitz
aharon(AT)yahoo(DOT)com
http://www.allbetsareoff.com
—————————————-
Creative Cow Master Series DVD
particleIllusion Fusion Volume 1
available @ http://www.pIllusionFusion.com

[Danny Perez-triana]

all that does make sense. thanks, i have a better understanding of it now. but i’m still having a problem in my composition: when i set my layer to be matted (keyed footage that was rendered with rgb+alpha) using an alpha matte as the tutorial calls for, instead of getting the above layer (interference) within the shape of the person, only that layer appears, meaning my matte layer doesn’t appear at all.

i’m at a loss right now. any help?

ignacio

[Aharon Rabinowitz]

Well, your matte layer should be invisible. That’s the point. You set another layer (Footage)to take it’s transparency from the layer above it (The matte layer), and the matte layer turns of it’s visibility. Otherwise what would be the point? If your matte layer was visible, it would block your matted layer from being seen.

Maybe I misunderstood your problem.

Why do you need to see your matte layer? Don’t you want to see your matted layer with the transparency it got from the matte layer?

Please explain, and I’ll try to help.

—————————————-
Aharon Rabinowitz
aharon(AT)yahoo(DOT)com
http://www.allbetsareoff.com
—————————————-
Creative Cow Master Series DVD
particleIllusion Fusion Volume 1
available @ http://www.pIllusionFusion.com

[Danny Perez-triana]

the effect i would want for some actors i’m shooting against a green screen is to have them move around but then have them appear as broken video signals.

what i want to get, and at least what is shown in the tutorial https://crewoftwo.com/making/effects/hologram/index.html , is that the interference layer (my matte layer), will fill in the shape of the keyed footage (the sith dude) in the layer below. so i would see the outline of the person but it would be filled in with the interference. so i guess what i want is potentially contrary to how these mattes work, meaning i want the interference to fill in opaque, the keyed footage.

i could then just duplicate the layer without the matte and reduce the opacity a bit to get this mixed video reception effect (the tutorial says to toggle the eye icon next to the layer to bring it up or down, but any time i click on the eye it either goes on or off)?

i thought i understood it as, by rendering the keyed footage with its alpha channel, when i selected alpha matte, the matte layer would automatically set itself over the footage of the keyed person.

thanks for bearing with me, it’s a big help

ignacio

[Aharon Rabinowitz]

OK, I think I understand. I was under the impression you wanted the acxtor to be seen, not the interference. You want the interference to appear with the shape of the person.

Key out the footage. This will be your top layer, and also the matte layer.

Either use a picture of interference or make a new solid, and apply the noise effect to it.

Then tell noise layer to use the above layer as an alpha matte.

Yeah, the eye icon this is incorrect, if what you are saying is true- i haven’t had time to read the tutorial.

Also, think about using layer blending mode like screen or add on the actor if you place him on top of the noise.

Hope that helps.

—————————————-
Aharon Rabinowitz
aharon(AT)yahoo(DOT)com
http://www.allbetsareoff.com
—————————————-
Creative Cow Master Series DVD
particleIllusion Fusion Volume 1
available @ http://www.pIllusionFusion.com

[Danny Perez-triana]

ok, so i got the interruption to fill in the form of the person (i’m using a still for now, since i don’t have any footage against a green screen right now). thank you so much.

my question is this: in terms of dealing with footage of dancers against a green screen (lots of movement), i fear a roundabout way of getting this effect. something i did different to avoid the screen just filling up with the interference image when i selected alpha matte was took out the background i had of the still of a woman. so when i rendered it with an alpha channel, the track matte only filled in the form of the woman not the entire screen.
i assume(?) this is because ae only recognizes the woman as the image in the composition and the background of the composition (regardless of color) would not be matted when an alpha matte was selected?

in terms of this: how would i go about getting this effect for dancers moving pretty fast: as i understand it:
1) i would have to take the footage of dancers against a green screen. key out the green, so that in my composition window the dancers were the only image set against whatever background color i had selected for the composition.
2) render this out with an alpha channel.
3) bring that back into ae.
4) place it above whatever i was using for interference in the timeline.
5) select alpha matte, and the dancers should be filled in with interference?

i guess i’m afraid of a double key: that i would have to create a separate image for the dancers to do this effect, and then key that again to put them on top of a background with this effect running.

i’m sorry if i’ve been confusing, it’s very generous of you to give me some of your time,
i hope you had a good day.
ignacio

[Aharon Rabinowitz]

I’m not sure I understand what you mean by a double key. Why would you need to key out the BG twice?

It should be pretty simple.

– Film them on Green screen (or if that’s not an option, Film them normally, and then – yikes – rotoscope them out of their BG)

– use AE’s Keylight effect to remove the greenscreen BG.

– Then just do what we did – use their shape as the matte for the noise layer, or apply a noise effect directly to the keyed layer.

If you do keep it on the same layer, Once you key out the BG, most effects respect your new alpha channel (The one created by the keying). Just make sure the new effect comes after the keying effect if it’s on the same layer.

You’ve already conquered this hurtle of making the effect work for a still – it’s really no different for motion video.

—————————————-
Aharon Rabinowitz
aharon(AT)yahoo(DOT)com
http://www.allbetsareoff.com
—————————————-
Creative Cow Master Series DVD
particleIllusion Fusion Volume 1
available @ http://www.pIllusionFusion.com