After Effects Gradient Mask

[bleutuna]

This is something so easy to do in Photoshop, that I'll be floored if it can't be done in After Effects: I want to do a simple fade on a layer, top to bottom - in Photoshop, I'd create the mask, and just add a simple black to white gradient. Easy peasy.

In After Effects? I have NO idea how this can be done. I've been searching the web ad nauseum, all to no avail. Anyone know?

 

[MiniMan13]

Generate Ramp!

 

[bleutuna]

Well, I did that, and it just made my layer a gradient But I want the MASK to be a gradient

 

[ProLost]

Put the ramp effect on a solid and use it as a luma Track Matte.

-Stu

 

[kai]

...or set a rectangle mask and feather it

 

[Steve_Arm]

It's called Linear Wipe under the transition FX.

 

[Matt Grunau]

Put the ramp effect on a solid and use it as a luma Track Matte.

-Stu

This is probably the closest route to what you are wanting in a Layer Mask type feature from Photoshop.

But to expand a little on Prolost's tequnique you would

1: Create a new solid and position it directly above the layer you wish to use the "mask" on. It's crucial it is the layer above, otherwise it will not work.

2: Use the Ramp effect and define your gradient. Black and white only, where, like Photoshop, black will be transparant and white will be 100 opaticy.

3: Hide the solid layer.

4: Make sure you Modes column is visible in the composition

5: To the right of the blending modes is another drop down menu. From that, select Luma Track as Prolost suggested.

That should do it. Also, if you needed some portions removed/made invisible and a simple gradient would not work, do what kai suggests and use masks. If that is still too limited, (working with multiple masks can give me a headache) you can create a black and white image in Photoshop, import it in and use it where the Solid Layer would be. Also, you are able to use layers, blurs, and other AE filters on that layer to change it's Masking effects on the underlying layer. That can be handy as well.

Lastly, you can also use AE's painting to create the layer, and that would work as well, though you may need to precompose that layer first.

Anyone know if precomposing a paint layer is necessary in this instance? I cant remember off the top of my head, and am not on my work maching.