Creating Complex Background Knockouts

Complex images cannot be dealt with using common selection methods like a magic wand etc. Neither it's possible to create a path of
such complex images using pen tool etc.

In this tutorial we are going to knockout the background sky from the image below.

Press Ctrl+J to duplicate the layer.

Goto Image>>Adjustment>>Threshold...

Move the threshold slider towards right so that image converted into more of a black and white image.

Select black color by magic wand tool.

From Select menu click on Save Selection.

Name it as tree.

Double click on background layer to unflatten it.
From Select menu click on Load Selection. Select tree as the selection.
From Edit menu click on copy.

Create a new file by pressing Ctrl+N.
From Edit menu click on Paste.

The complex area that was visible behind the leaves has been knocked out. Now you can remove rest of the unwanted area using Eraser tool.
Select background layer and fill it with any background color, gradient, texture or image. It will show through the leaves perfectly.

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