Photoshop: How do you make a blur not go over a layer under it without changing the layers level?

Question

Photoshop: How do you make a blur not go over a layer under it without changing the layers level???

I remeber doing this on Photoshop but I can't remeber how to do it or I just did it a different way and forgot but I have looked every where and kind find anything about this.

Answer 1

I don't know exactly how your document is set up. If the light square is on a separate layer and has transparent background, you could do one of the following two things:

Create a Clipping Mask

• Place the mouse cursor between the layer with the lines and the layer with the square which you want to confine the lines to.
• Hold down Alt and left click.

Create a Layer Mask

• Hold down Ctrl / Cmd and left click the layer with the square to select all non-transparent pixels of that layer.
• Select the layer with the lines and click the Add layer mask button.