Photoshop is synonymous with image editing, and with the addition of adjustment layers to its arsenal, Photoshop has even more flexibility than ever before. For the addition of adjustment layers, when you would edit an image, you would have to duplicate the original layer for safe keeping, and when you made an adjustment to its Hue/Saturation, Color balance, or any of the other adjustment settings, they were permanent. To go back and edit them, you would have to use the undo command, but if you had saved and closed the document, the image was altered permanently.
Now, adjustments are in control with what are called Adjustment Layers. You can find the adjustment layers on the Layers panel at the bottom, and in the center as shown below.
When you click the icon, a drop-down menu will appear, where you can select different adjustments that you can make, including Solid Color, Gradient, Pattern, Color Balance, Exposure, Brightness/Contrast, Vibrance, Black & White, Channel Mixer, Photo filter, Curves, Levels, Invert, Threshold, Posterize, Gradient Map, and Selective Color.
In the example, I chose Hue/Saturation. Notice that when you click the icon, it creates a new layer above the layer that you have selected when you clicked the icon. It titles the new layer by the name of the adjustment and the number of that adjustment. When you are editing complex images, you may end up having several adjustment layers of the same type. For example, if you are adjusting color in an image, you may have one adjustment layer compensating for an area of your image that has too much green, and another adjustment layer correcting another part of the image that has too much yellow. This is fairly common when editing images. In this case, they will be named in succession. This is Photoshop’s way of helping you keep track of your adjustment layers.
To view the settings for the adjustment layer, you can double-click the slider icon on the adjustment layer itself, or you can bring up the adjustments panel by going to the top menu bar, and select Window>Adjustments. Select the icon for Hue/Saturation. You should see a panel like the one below:
The panel looks just like the dialog box found when you use the adjustment menus, but there are a few subtle differences. There are a few icons across the bottom that you will want to pay attention to. The left arrow will send you back to the main panel with the different adjustment layer choices. If you have distorted your panel, the 2nd icon (The folder and arrow) will reset the panel to its standard view.
The 3rd icon, the black and white circle, toggles whether the adjustment layer effects all of the layers below, or if it is clipped to just the single layer below. Clipping it to the layer below means that it only affects the areas on your Photoshop document found on that layer. If there are areas of that layer that are transparent, they will not be affected.
The 4th symbol (The eyeball) toggles the visibility of that adjustment layer, just like the eyeball symbol on the layers panel itself. The fifth icon, The eye with the curved arrow toggles your last setting, so if you are unhappy with the adjustments that you have just made, you can set them to the previous state. The 7th icon (the circular arrow) resets the entire adjustment panel back to the default settings. This is handy if you’ve gotten off track and just want to start over with your adjustment. The trash icon, of course, trashes, or deletes the currently selected adjustment layer.
The main point of having an adjustment layer is to be able to go back and make changes to your adjustments easily. You can do this simply by double-clicking on the adjustment layer icon itself, in the Layers panel. There is a huge advantage when using adjustment layers and the adjustment panel instead of simply using the adjustment settings found under Image> Adjustments. The first and obvious advantage is that you can edit and tweak your adjustments as many times as you want. You have the ultimate flexibility of being able to layer your adjustments as many times as you want. You can also delete an adjustment layer, and duplicate it just like a normal Photoshop layer.
Another huge advantage that you will have when using an adjustment layer, is that you can mask your adjustments so that they only affect a portion of the image that you are working on. The mask is circled in the example below:
This mask automatically comes up when you create an adjustment layer. It is prefilled with white, which means that the entire adjustment layer is visible. Below is an example of my Phoenix creation, you will see the original image, the image with the adjustment layer in its entirety, and the image with half of the adjustment layer masked out.
1.The original image:
2.The image with the full adjustment layer:
3.The image with half of the adjustment layer masked:
The great part about using this method is that the mask used on an adjustment layer is just like the mask used on any other layer. You can use a gradient, paint on the mask with a soft-edged brush, and you can blue and feather the mask to blend your adjustments, making them smoother and making them appear to be more natural.
Finally, one last reason to use adjustment layers is that you can use blend modes on your adjustment layers. This is especially handy for creating effects that would be difficult to create otherwise. You can use any blend mode that is available to a normal Photoshop layer, so the possibilities are literally endless. I used the same image as above, with the same adjustment layer, but I removed the mask so the full effect can be seen:
Above, I changed the blend mode to multiply, and when doing so, the image below was the result.
The result is a golden color that may be difficult to achieve otherwise with Photoshop. In places, the phoenix almost appears metallic. I clipped the adjustment layer to the phoenix layer, so it only affects that layer, and not the layers with the black background or the smoke. Combining these techniques is essential to creating amazing effects in your designs inside of Photoshop.
Using adjustment layers gives you the ultimate flexibility in your work, by allowing you infinite opportunities to edit your adjustments, giving you the ability to use masks and the ability to use blend modes. By doing this, you can edit your images non-destructively and efficiently.