FEBRUARY 19, 2002
Photoshop Layer Styles and Alpha Channels
You've created a graphic in Adobe Photoshop, and you want to bring it into your video editing or compositing package. Not a big deal, right? The problem is that you've used a Layer Style in Photoshop (such as Drop Shadow), and your alpha channel, upon import to your video editor, seems to clip the transparency. Where did the effect go, and what can you do about it? As the host of our Photoshop forum here at DMN, I encounter this question quite frequently. Rather than continue answering it every single time, I've decided to provide you with this quick tutorial.
If you're using more recent versions of Adobe software, such as After Effects 5.5, there really is no issue. (See below for working with older compositing or editing packages.) It's just a matter of how you import the footage. Instead of importing your Photoshop file as "footage," import it as a composition. When you import as footage, you get either a single, flat layer, or a layer containing no layer effects whatsoever. But importing the file as a composition gives you the equivalent of a multi-layered piece of footage with each element of the file--including effects--remaining fully editable. Do do this, Control-click (right-click) in your Project window in After Effects, and select Import > File. (Or select Import from the File menu, or simply type Command-I.) When the dialog box appears, as in the image below, choose Import As: Composition from the pull-down menu.
Now in your Project window, you'll see two new items--a file and a folder both called "[yourfile].psd." To use this in your main composition, simply drag the Composition file into your main composition's Comp window. The footage will then appear in your main timeline as a single layer, though it is, in fact, a multi-layer file.
If you'd like to edit the file or place keyframes on a layer by layer or effect by effect basis, you simply double-click on the Photoshop composition file in your Project window. This will add a tab to your main timeline, providing you with keyframe options for each individual layer and effect of your Photoshop composition. Any changes you make in this timeline will magically show up in your main composition.
So the process is really a simple and flexible one--provided you have a recent NLE or compositing application.
But what if you don't? What if you're using a dated version of Premiere, for example, that doesn't give you these kinds of import options? That's when you have to do a little work in Photoshop itself.
Now, a lot of people immediately jump at the "Flatten Image" command in Photoshop as an expedient means of rendering effects for output. But there's a problem with this, which any of you who have tried this have encountered: You lose your transparency. But there are three better ways to approach this problem, each one appropriate for differing circumstances.
The first and most simple is not to flatten the image but to merge the layers of your Photoshop document. You can do this easily in the Layers palette by clicking on the flyaway menu, and then selecting "Merge Visible."
Of course, this assumes you have more than one layer in your document to begin with. If you don't, simply click on the "New Layer" button in the Layers palette. This will give you a new, transparent layer, which will then enable you to merge visible layers.
The result will be a "flat" image consisting of a single layer, but your transparency will remain intact. This approach is fine, if you just have a single-layer file or don't plan to keyframe individual layers in your Photoshop file once you bring it into your NLE. But what if you do want to keyframe on a layer by layer basis and don't want to flatten your Photoshop image?
Move on to plan B.
Plan B is a bit more labor-intensive than Plan A. It involves Layer Sets rather than just layers. Here's how it works.
1 2 Next
Related sites: AV Video Creative Mac Digital Media Designer Digital Producer Digital Video Editing The WWUG