How Do You Create a Comp from Layers in After Effects?

To create a composition (comp) from layers in After Effects, you pre-compose the selected layers.

Here's a breakdown of the process:

1. Select the layers: In your Timeline panel, select the layers you want to include in the new composition.

2. Pre-compose: You have two ways to initiate the pre-compose process:

   • Menu: Go to Layer > Pre-compose...
   • Keyboard Shortcut: Press Ctrl+Shift+C (Windows) or Command+Shift+C (Mac OS).

3. Pre-compose Settings: A dialog box will appear with pre-compose settings.

   • Composition Name: Give your new composition a meaningful name.

   • Attributes: This is the crucial part. You'll usually want to choose one of the following options:

     • Leave all attributes in [your original composition name]: This moves the selected layers into a new composition, but leaves their keyframes and effects in the original comp, applied to the new pre-comp layer. This is useful when you want to adjust the animation of the pre-comp as a whole within the main composition.

     • Move all attributes into the new composition: This moves everything, including keyframes and effects, into the new composition. This is useful when you want to isolate the selected layers and their animation for independent editing.

   • Open New Composition: Check this box if you want After Effects to automatically open the newly created composition.

4. Click OK: Your new composition will be created based on the settings you selected.

In summary, pre-composing is the primary method for creating compositions from existing layers in After Effects. The key is to understand the 'Attributes' options during the pre-compose process to achieve the desired outcome.