Alternative to transparency shapes layer in After Effects

[Tomasz Zając]

Hi!

I have a problem, and this problem is finding the simmilar effect or bypass to achieve the same result as option in Photoshop called "transparency shapes layer". I followed the tutorial how to make the sun within the trees, and it requied this option turned off, blend mode to color dodge, and the layer to be cirle with big gradual fade on alpha on the edges, feather it's called I guess...? So... in Ae I decided to make it the same way to degree. It did not work very good. I changed blending mode from color burn to its classic version, and changed layer from adjustment layer to normal layer. It did better job. Pretty good actually. But the best effect was when I used effect called "Gradient ramp" and switched to radial ramp option. Well, this made a difference! Hell, it was almost perfect if not perfect! But I am just curious if it is possible to make this when I am working in alpha, not black and white. I achieved what I wanted, and created this post to save the solution for the others for this case, but I would like to know if there is an option to work just on alfha channel. Even if there is a way to adjust alpha just like effect "Levels" do. Or the blending mode, which works on the alpha in a way, that the more something is transparent the lesser impact it has on the layer below. Just like the "Fill" option next to opacity in photoshop. I tried to use in Ae "Blend" effect, and it, I think, worked to certain degree. But not ideal solution. So, does anyone have any idea how to achieve the effect in which the more transparent something is, the lesser it impact the layer below while the first one has the blending mode on? The impact like "fill" in Ps, not opacity. I want to underline it.

[Rick Gerard]

I am not completely following you. You can add a mask to the layer that has an effect applied, then add Compositing options to that effect in the timeline. There's a plus sign at the bottom of the effect properties. This will pick a mask, stop it from masking the layer, and limit the effect to just the area of the mask. You can also adjust all of the other mask properties from Feather and Expansion to Transparency.

Combine this with Blend modes, and you have a huge amount of control over how the effect is applied to the layer. 

[Tomasz Zając]

I think I complicated everything I thought of too much to degree where I didn't realise, that I found the solution myself, and even recorded it and sent it here. I just needed to adjust feather and scale. But is there a way to control an alpha gradient? Just like "levels" allow you to modify the luminance. To adjust how alpha throughout the alpha gradient should be distributed.

[Rick Gerard · Accepted solution]

You can add Curves and adjust the curve on just the Alpha channel. You can do the same with Levels. Viewing the Alpha channel in the Comp panel will show exactly what you are doing to the Alpha Chanel. I use this a lot when I composite lights, gunshots, and explosions in those kinds of composites. The biggest part of the trick is using multiple layers.

That's nothing but a red rectangle on a shape layer with Gaussian Blur and Alpha Channel manipulation.

[Tomasz Zając]

Thank you! Sorry, I don't know how I didn't realise there was an option like that, I have no idea how could I be so mindblank back then...