Is there a way to keep a mask STILL on a layer, while the layer moves?

[Chris Smith]

either animate the anchor point of the layer instead of the position. Or copy and paste the mask to a solid then use the solid layer as an alpha for the diver layer.

Alphas are an essential part of compositing, so I’d “dive” right in now. Cheap pun. I’m tired.

Chris Smith
https://www.sugarfilmproduction.com

[Daniel Haskett]

Hi there,

Thanks for your help, I was just wondering how do I make the solid layer an alpha layer for the diver? Ive been trying to do it but cant work it out. Ive made a solid with a mask in, does that go above or below the diver and then do I go to switches/modes and then set it to alpha matte? When I do that it doesnt seem to work…does making it alpha make the solid invisible? I wish I knew how to do this, it sounds so simple! Please help 🙂

Thanks

Dan

[Daniel Haskett]

Oh and also I just tried animating the anchor point but the mask still moves with the layer…do you know why that is?

cheers

dan

[Daniel Haskett]

Ok so…. I seem to have worked out the alpha thing now, the only question I have is this. When you make the solid an alpha, the layer above seems to adopt the colour of the alpha solid…so how do you make it not adopt its colour?

Also what exactly does compositing mean? ;)I like to think I know a bit about after effects, but more for animation not live action stuff…

cheers

dan

[Steve Roberts]

When alpha matting, the shape of the layer above “cuts out” the layer below. You will then see the lower layer only, but it will shaped like the upper layer.

The upper layer is the matte layer.

The upper layer should have its visibility (eyeball) switched off. Normally, this is done automatically.

There should be no other layers between the pair in the layer stack in the timeline.

Basically, compositing is the assembling of image layers into a whole, or “composite” image. Search Amazon for “compositing” and “Ron Brinkmann”.

Steve

[Chris Smith]

Dan, it sounds like you are not using the track matte but using multiply or something if it is picking up the color of the solid.

Alpha channels are equally important to animation as they are to live action. This is basic stuff if you look through your manual. It’s all in there well explained. Also pick up the unofficial AE manual which is the books from Chris and Trish Meyer. Check amazon for that. These books and your manual will tell you so much about the how to’s so that your friends at the Cow can explain the whys and when tos if that makes sense.

Chris Smith
https://www.sugarfilmproduction.com

[Daniel Haskett]

Hi there Chris,

I appreciate all your help, its been really helpful but I just dont understand when I make a track matte it is changing the colour of the layer above it. I PROMISE I have a made a red solid and then made a red mask from this and made it an alpha track matte in the Switches/Modes section, it does work apart from the layer above now becomes red…is there anything Im doing wrong? Please help!

Thanks

Dan

[Steve Roberts]

(Steve barging in)

Daniel, dupe the comp and delete all layers in the dupe except your masked solid (above) and your footage (below).
You should be working in this stripped-down dupe, just to eliminate distractions.

Enable the checkerboard switch at the bottom of the comp window.
Make the TrkMat button for the footage (lower layer) “none”.

Make sure that your masks create a silhouette of the masked solid layer. I assume it should look like a red diver on its own?
Make sure that the masked solid is above the footage in the timeline.
Make sure the masked solid is set to normal mode.
Make sure the Trkmat button for the footage layer is set to “alpha matte”.
Make sure the masked solid is not visible. Eyeball off. This should happen normally.
Make sure that the footage layer is visible. Eyeball on.

Go back to the manual and re-read just to make sure. The process is very simple:
1. draw a mask on the upper layer.
2. Set the TrkMat for the lower layer to alpha matte (appropriate for your case, I believe).

It’s quite simple, really. If you still have trouble, start from scratch.

Steve

[Daniel Haskett]

Wow Steve, thanks for barging in, I really appreciate it!

So I just tried what you said and its great, amazing how simple it is! The problem I was having is simply that I had the layers in the wrong order, the masked solid was below the footage, so I guess that explains it all! This is great, its gonna save me so much time, and time is very precious at the moment!

Thanks so much again 🙂

Dan