Reverse Iris wipe in After Effects

[DDRDiesel]

So I've come across a roadblock in my current AE prject where I need to do an iris wipe to reveal a layer underneath, but the wipe needs to go from the outside into the center, rather than inside out.  There's no "reverse" button in my transition properties, and I found one post using expressions that doesn't work in my project either.  What's the best or easiest way to go about what I need to do?

[Rick Gerard · Accepted solution]

Put the Iriis wipe on the layer you want to reveal, move it to the top and animate the radius from its maximum value to zero to reveal the layer from the outside in.

A second option: Add a solid to the project, apply iris wipe to the solid, then use it as a track matte and choose Alpha Invert.

[DDRDiesel]

Thanks for the tip!  I never would have though about covering the first scene with the one being revealed, genius!