Sorry if I missed a part of what you were saying, but I think it's a situation where you need to use a white solid layer as the layer with the matte. Then put a black solid behind those layers - then you will have white lines on a black background.
Hi Greg, thanks for your response. Doing what you suggested gives me a white foreground.
Here is my cartoon in a black composition
When I add a white solid it looks like this...
(the blue is just me indicating where the comp ends.)
Here is what the after effects panel is...
Now what I wanted is like image 2 but instead of the surrounding being white. I want it black. Kind of like this...
Hope that makes sense.
Thanks again so much for your help
Does Find Edges on the original drawing give you the look you want? Try turning on Invert inside Find Edges.
Thank you again for your response Greg.
Alas no, that just emphasised the edges.
The inv luma is doing what it should in that it is turning the white part of the layer transparent and giving the black part the colour of the solid the inv luma is being applied to which is black. What I would like it to do is turn the black part of the image to white whilst having the solid so to speak be black.
I wonder if turning the cartoon into a (photoshop) image where the white is transparent work?
Thanks again for your help, all other suggestions appreciated. I am sure there is an answer?
What I want is for the lines to be white but the layer solid to be black.
Use the Invert effect. You get white lines on black. If you don't need transparency in the black portions of the image you're done. No track mattes needed. Add a black solid to the comp if you want an opaque black background.
if you do need transparency you can add the Shift Channels effect and set the alpha to Luminance. The black becomes transparent. You can check it by clicking on the checkerboard setting at the bottom of the comp window.
There's a basic flaw in your concept. When you create a matte you loose the outlines of the drawing because you either have the background (black) visible and a hole where the white is or you have the foreground visible (white) and a hole where the black is. For your effect to work you need to create some lines between the black and white.
A more effective way to create a luma matte for a high contrast black and white drawing is to use set matte. Combine that with Refine Matte or Matte choker and you can create some outlines. Use Screen to make the black dissapear or Multiply to make the white dissapear and you end up with only the lines generated with the matte choker visible. You have to hope that you've got clean enough lines and enough detail to not end up with Jaggies....
This will give you kind of what you want. It's the closest you can get with the kind of artwork you've got. Take a close look at this screenshot and duplicate the settings. It should help.
Thank you so much Rick! That got it spot on. Learned quite a bit from your help.Much appreciated.
Thanks to Greg too mate!