Garbage matte?

[Rakesh Malik]

How do you add a garbage matte in Boutique? I tried with shapes in the green screen node, and that seemed to disable the chromakey itself; without the shape, the backdrop is gone, with the shape, the backdrop is visible. What am I missing?

 

[jan1]

Not at my system right now. This old tutorial has good detail on it: 

 

[jan1]

At 7:30 in the video he explains the key point. In the shapes interface you need to select 'keep' with the input alpha so you can combine the green screen alpha and the shape.

[Rakesh Malik]

Thanks! That had what I was looking for, but I was searching the wrong playlist.

The shape behavior is also very unintuitive. Set the shape's mode to "intersect" and create a shape, it pops back to add, which isn't correct. It makes you think it's broken, when in reality it's just being obnoxious.

And if you have, say, the Comp3D node active, select the green screen and add a shape, the shape ends up making no sense whatsoever. You have to make sure that you have the green screen (in this case) node active when you add the shape, then transforming that clip with the transform widget on the Comp3D node works as expected. That part makes perfect sense once you get used to the active vs selected node thing in the eval tree.

Now to figure out how to use the edge build node to add a little bit of light wrapping, then figure out how to clean up the dark line around the foreground element... ?

Making progress!

 

[Cristobal Bolaños]

Hi @Rakesh Malik!

On 8/24/2019 at 11:03 AM, Rakesh Malik said:

Now to figure out how to use the edge build node to add a little bit of light wrapping, then figure out how to clean up the dark line around the foreground element...

You have a bit more information about the Mistika keyers in the following tutorial. The Edge Build effect is explained from the minute 25th:

On 8/24/2019 at 11:03 AM, Rakesh Malik said:

The shape behavior is also very unintuitive. Set the shape's mode to "intersect" and create a shape, it pops back to add, which isn't correct. It makes you think it's broken, when in reality it's just being obnoxious.

Can you explain a bit more about this behavior? I'm trying to reproduce it and I do have that intersect function. I mean, I create first a shape, then, I set "shape combine" to intersect and the result of the alpha is indeed the intersect of the two shapes I have created.

On 8/24/2019 at 11:03 AM, Rakesh Malik said:

And if you have, say, the Comp3D node active, select the green screen and add a shape, the shape ends up making no sense whatsoever.

Indeed, the GreenScreen effect is not developed to interact with the shapes. The workflow as usual when working with alphas (combining, dividing, subtracting them and so on) is to export the alpha you have created with your GreenScreen with the Show Alpha effect. Then, in that layer you can create the shapes you want and they will interact. Also, you have the Channels effects in order to do multiple operations regarding alpha or the RGB channels. Finally, the External Key Effect is the one you have to use to introduce a particular alpha in a clip. Or maybe you want to use that Alpha in the Color Grade node, in that case, you have to go to the Output tab inside the Keyer window and set Enable Ext Key > Mask > A. 

Hope you find it useful!

Cheers,
Cristóbal

 

[jan1]

On 8/24/2019 at 5:03 AM, Rakesh Malik said:

That part makes perfect sense once you get used to the active vs selected node thing in the eval tree.

Yes, you do have to keep the eval tree open and select appropriately. It's all logical once you wrap your head around it, and quite powerful. Many other apps have similar concepts for selecting visual scope vs. edit scope. Avid track panel, Silhouette's tree, etc. These are just the UI quirks of large applications that take some time.

[Rakesh Malik]

Christobal, thanks for referring me to that tutorial. I'll peruse it shortly.

What I found unintuitive is that when I set the mode for the shape before drawing the shape, it got reset. Once I realized that I had to reset it, it made sense.

The eval stack takes some getting used to, but I agree that it's very powerful, but it's the transparent way that you can go back and forth between the eval stack and the node tree that appeals to me when it comes to compositing. 

I'm still getting used to how to manipulate and export (maybe not the right word) alpha channels from the color node. I used the green screen effect because it worked so well though... Mistika's keyers are very nice to work with.