Export Shadows with Transparency

[Steve Johnson]

What is your export process? Are you exporting with a codec that supports alpha? If so, perhaps you should ensure you are exporting with a straight channel, and not premult, if you are going to be matting against wide range of background colors.

Also, double check that when you enable the transparency grid in your comp what you see as transparent is what you want.

CS3 – Mac
C4D

[Paul Conigliaro]

I’m not sure if this is possible, since AE needs to know where to place the shadow, and if you turn off that temp background, there’s nothing to cast the shadow on. I can look into it tonight or over the weekend, but the only thing I could think of trying to do is creating a shape layer then turning the fill down to 0% opacity. But I’d doubt that would work.

Did you consider faking it with a duplicate text layer in black & blurred a bit, then animated either by hand or with expressions to match the movement of your original text layer.

CS3, FCS2
[Note: Using Particular, 3-D Stroke, and now Form do not instantly make your designs “teh awesome.”]

[Bret Williams]

You would need some sort of a “accepts shadows ONLY” parameter like the casts shadows ONLY parameter. But unfortunately we don’t have that capability that I know of.

There’s an idea in there somewhere though. Maybe make the temp background layers white. Adjust the shadows on your other layers to suit. Hopefully to cast shadows of a good medium gray. On all the shadow casting layers, set their material properties for shadow to casts shadows ONLY. Render that and you’ll have a nice black and white image to use as a luma matte in FCP for a black layer.

Also render your project normally with the temp (white) layers off and an alpha matte.

But if you’re just looking for a basic nondescript shadow, why not just precompose the project and add a shadow effect? That’ll render out wihout any sort of temporary background.