Part of the rationale behind layers is the potential to selectively decide which layer to combine with which to compose a final image. Layers let you create many different image edits, and try them out in different combinations without affecting the underlying image.

 

The Fish.psd image from the Photoshop CS samples folder contains eight separate layers. These layers can be seen in the layer palette shown at the right of the image. You will notice though, that each of the layers has an eye icon visible at its left. These eye icons control the visibility of the layer.

 

Put simply, if the eye is visible at the left of a layer item in the layers palette, the given layer will be visible in the image. Of course, the part of a layer that does not contain any image data is transparent. When we use terms like visible or hidden with respect to layers, we are referring to the image information on the layer. (It makes no sense to display or hide a layer that does not have any information on it, as it would be completely transparent in any case.)

 

To hide a layer, simply click on its adjacent eye icon. The eye icon will disappear from the layer item in the layers palette, and the image data associated with that particular layer will not be visible in the image. The Fish image is a great image to play with in this regard, because it has a number of layers with different image data on each.

 

 

Can you notice a difference between this Fish image and the previous one? The second layer from the top in the layer palette has been set to invisible (no eye icon). As a result, the white swirls in the original image are not displayed. It is important to point out that the data for this layer is not gone; it is just hidden from view in the image.

 

To make a layer visible again, simply click on the small empty square at the left of the layers palette that is associated with the given layer, (the square that used to hold the eye icon when the layer was visible).

 

In reference to the image shown above, you would click on the empty square at the left of the layers pallet, second from the top. This would make the corresponding layer (shown in the layers palette highlighted in blue) visible again.

 

 

If you would like to hide all of the layers in an image except for one, make the layer you want to view active (highlighted in blue) and press the Alt key while clicking the eye icon. All of the other layers will be set to invisible. If you click again on the same eye icon while holding the Alt key, the other layers will be set to visible again.