Create radial opacity ramp using just expression

[Anmol Mishra]

Hi.

I want to place a still on layer 0 and a video on layer 1.
I want the opacity of layer 0 to vary from 0% in the center to 10% at the edges.

Distance from a point is

length(thisComp.layer(0).position, [960,540] )

Normalize this over 1.

length(thisComp.layer(0).position, [960,540])/length([0,0], [960,540])

And transparency from 0-10% would be

length(thisComp.layer(0).position, [960,540])/length([0,0], [960,540]) * 10

Does this sound right ?

I am essentially trying to create an opacity ramp that goes from 0 in the centre to value x at the extremes.

Thanks!

[Anmol Mishra]

Got the answer

https://forums.adobe.com/thread/1928460

Easier to do this without expressions