After Effects Quick Tip: Link Focus Distance to Layer

Save time! Link up the focus distance of layers to a 3D camera in After Effects.

If you do a lot of work with 3D cameras in After Effects than you probably know how much of a challenge it can be to work with focal distances, especially if you are working with an incredibly shallow depth of field.

You’ve probably spent a lot of time trying to scrub through the focus distance to find the exact point where your object is located. This method can be extremely time consuming and taxing on your computer – it’s definitely not recommended.

To avoid this problem you can use the ‘Link Focus to Layer’ button in After Effects. As the name implies, this tool will link the focus distance of your camera to the position of the layer in 3D space. This is especially important if your camera or 3D object is moving around in Z-space.

By following these quick steps you can learn how to use the ‘Link Focus Distance to Layer’ feature in After Effects:

1. Create a Camera

Go to Layer>New>Camera. You can now adjust the various camera options in the camera menu. Typically if you are using the ‘Link Focus Distance to Layer’ feature it’s because you are working with a shallow depth of field, so for the following example we will turn depth of field on.

2. Select Camera and 3D Layer

Select the camera and 3D layer that you want your camera to follow.

3. Link Focus Distance

Navigate to Layer>Camera>’Link Focus Distance to Layer’. After Effects will now apply an expression to the focus distance of the camera. This expression will automatically adjust the focus distance of the camera to match the position of the layer, even if the layer moves.

It should also be noted that this technique works even if you have parented your camera to a null object.

Want to learn more quick tips in After Effects? Check out the After Effects section of the PremiumBeat blog. We have hundreds of articles and tutorials entirely dedicated to helping you become a better video editor and motion designer.

Have any other tips for working with 3D cameras in After Effects? Share in the comments below.