Start Shake.

Choose File > Import Photoshop File.

When the browser opens, select the choppers.psd file located in the Lesson11/multi_layer folder.

A tree is loaded into the Node View consisting of four clips plugged into a node named Composite.

Hover your cursor over the Composite node.

At the bottom center of the screen, the Contextual Help window tells you not only that the node is named Composite but also that it is a MultiLayer node. It took the name Composite from the Photoshop file, but you can rename it.

Double-click on the Composite node so that you can see it in the Viewer and edit its parameters.

Rename the text in the MultiLayer parameter (at the top of the Parameters tab) from Composite to MultiLayer.

The MultiLayer node found in the Layer tab accepts an infinite number of input images, each layer containing its own unique settings to control the compositing mode, opacity, and channels. Because you may rearrange the layers via drag and drop in the Parameters tab, it also allows you to work using layer-based, rather than node-based, logic.

Take a look at the Parameters workspace.

Unlike other Layer nodes, the first input represents the background layer, the second input is the next deepest, and so on, until you reach the input farthest to the right, representing the foreground. When the nodes are inserted, they are stacked in the Parameters workspace as well, with the background at the bottom and the foreground at the top. Each layer has associated parameters and controls in the following order:

Parameters	Function
	shows the input of the image for that layer in the Viewer
	toggles the visibility for that layer
	solos the layer, making all other layers invisible
	turns off all layers above the current layer and keeps only the current layer and those below it visible
	dragging this icon changes the layer order
	the name of the input image node; by blanking it out, the node is disconnected, but the layer information remains
	the compositing operation for that layer
	deletes the current layer

Try out some of the layer functions:

Change the Compositing operation of the chop1_beam and chop2_beam clips to LinearDodge.

Toggle the visibility of the chop1_beam clip.

Solo the choppers clip.

Okay, so far you brought in a Photoshop file that automatically hooked up all of the inputs into your MultiLayer node. What if you wanted to add inputs to a MultiLayer node from scratch? All you have to do is drag the inputs into the + sign on the top of the MultiLayer node, which occurs when the cursor passes over it.

Choose File > New Script and click No when prompted to save the script.