Layers can be roughly described as being like transparent sheets, on which you can paint, add image effects, make colour changes, and perform other image operations. Multiple layers can be created and overlaid on each other, combining their individual effects. The great thing about layers is that you can adjust, edit, or remove one layer without affecting the other layers, or the original underlying image.

 

The layers palette is used for creating and manipulating layers. Layers are a central concept with Photoshop, making the layers palette one of the most important Photoshop components.

 

To create a new layer, click the menu arrow at the upper right of the palette, and then click the new layer item in the menu that appears. You will now see a new layer dialog box.

 

 

 

 

 

Enter a name for the new layer and click the OK button to create it.

 

You can now see a new layer added above the original layer in the layer palette. Beside the layer, you can see an eye icon, and a brush icon. When a layer has an eye icon present, it means that it is visible. If you click the eye icon, it will disappear and the layer and its contents will not be visible. Clicking the blank square where the eye icon was will bring it back and the layer will be visible again.

 

 When a layer has a paint brush present, it means that the layer is in edit mode, any brush strokes, colour changes or other editing effects will be applied to the selected layer. If you click the lock icon found just above the top layer in the list, the selected layer will be fully locked, (a small lock will appear at the right of the layer item) which means it cannot be edited. To unlock this new layer, select it and click the same lock icon that you used to lock it.

 

You will notice three more icons to the left of the lock icon (a checker board, a paint brush, and a pair of crossed arrows). You can click on one or more of these icons to lock a specific property of the layer. For example, clicking the paintbrush will lock image pixels, and clicking the crossed arrows will lock position. If you only lock one or more (but not all) properties of the layer, the layer will be partially locked, and a lock icon will be displayed at the right of the layer that is not as dark as the lock that appears at the right of a fully locked layer.

 

If the layer is unlocked, you can select it, and paint some brushstrokes on your image. If you click the eye icon to make the layer invisible, you will not see the brushstrokes (the contents of the layer you made invisible will not appear on the image).

 

To remove a layer, you can simply drop and drag it to the trash can in the lower right. If you want to create a new layer quickly, without going through the new layer dialog, click the new layer icon (the one that looks like a sheet of note paper with the lower left corner turned up) located just to the left of the trash can.

 

If you click on the right pointing arrow next to the small text field labelled Opacity, an opacity slider switch will appear. You can move this slider with your mouse to adjust how opaque (transparent) the contents of the selected layer are.

 

Here is an image, with the layers palette along side. The happy face painted on layer 1 is at 32% opacity.

 

As with other palettes, right clicking on the menu arrow in the upper right will reveal multiple options for working with layers. There is also a layer menu available from the menu bar (chose Layer on the menu bar) that contains multiple options and sub menus for working with layers. This discussion is just a brief introduction to the concept of layers in the context of the Layers palette. Layers in Photoshop CS are extremely flexible and rich tools with many possibilities that are a little too advanced and lengthy to take up at this point.

 

 

The channels palette lets you work with the colour channels present in an image. A colour channel could be described as the information contained in the image that relates to an individual colour.

 

The graphic at left shows the RGB (red, green, and blue) colour channels of the currently active image. This image is being used in RGB mode. If you switch to CMYK mode, the channels palette will display the CMYK channels for the active image. You can switch back and forth between CMYK and RGB by choosing Image->Mode-> RGB or Image->Mode->CMYK from the menu bar.

At the right are the CMYK channels for the same image. You can click the eye icon next to a channel to eliminate it from the image. Advanced users can perform many subtle and interesting image modifications by manipulating colour channels.

As usual, clicking the arrow in the upper right of the palette will display a menu of options for this palette.

 

The Paths palette is for working with vector graphics elements. These elements are normally created with the pen tools in the Photoshop toolbox and can take various shapes such as lines circles or freeform curves.

 

If you click the arrow in the upper right of the palette, you will reveal menu options that will allow you to save a path, delete a path, duplicate a path, or create a new path (these menu items can change depending on the path that is selected from the palette). You can also right click on a path item in the palette path list, and select duplicate or delete from the pop up menu. You can also simply drag and drop a path into the trash can in the lower left to delete it.

 

If you create a path and save it, the palette menu will provide options for making a selection with the path, and for applying strokes (painted colour) to the path. Paths are vector graphic elements, and are not to be confused with standard bitmap graphics as the same rules do not apply to both. There will be more discussion of vector graphics and bitmap graphics in lesson 4.1.