The Ins and Outs of Auto-Align Layers
Auto-Align Layers is one of those Photoshop features that can be used for many different tasks. First, we’ll use Auto-Align Layers to odd something to an image. Then, we’ll use this versatile feature to remove an unwanted element.
How many times have you been with another person and you wanted to take a shot of the two of you in front of some point of interest? Usually, you get this long arm extending from the camera in the shot. But let’s say you want a nicely framed shot, showing the two of you in a nice pose. You have no tripod and there’s no one around to ask to take the picture for you. Let’s start by enhancing this common situation.
step one: This first image shows a shot I took of my wife soaking up the ocean breeze. Great place for a couples shot, but there was only one chair and no one else around!
step two: I moved the chair to the opposite side and sat down. She then took this shot of me. Now there are two separate shots.
step three: In Photoshop, using the Move tool (V), drag one image over to the other image. It comes in as Layer 1. In the Layers panel, select both the Background layer and Layer 1 by clicking on one of them and Shift-clicking the other.
step four: Choose Edit>Auto-Align Layers. Note: The Background layer doesn’t need to be converted into a regular unlocked layer to use Auto-Align Layers. Upon implementation, the feature will automatically make the conversion.
step five: There are various modes available in the Auto-Align Layers dialog, but choosing the default of Auto is fine in this situation. Click OK, and the result is two image layers that are as close to perfectly aligned as possible.
step six: Now comes the point of all this—combining the two into one. Click on the top layer in the Layers panel to make it active, and apply a layer mask to it by clicking on the Add Layer Mask icon (circle in a square) at the bottom of the panel. Using the Brush tool (B) with black as the Foreground color, paint the mask over the area where the currently hidden chair is to expose the image below. Now there are two chairs.
step seven: When doing these kinds of things, it’s very important to look at the overall scene to make sure it’s working. Upon closer inspection of the image, you can see the shadow from the chair on the left running across the deck. The shadow should be cast over parts of the chair on the right, as well as my fingertips. To make the scene look real, these shadows must be created.
step eight: Click the Create a New Layer icon at the bottom of the Layers panel. Press D to set the Foreground color to black. In the new layer, use the Brush tool to paint black strokes to form the basic shapes of the desired shadows.
step nine: Set the blend mode for the layer to Multiply near the top left of the Layers panel. Lower the Opacity until it matches the tones of the existing shadows elsewhere in the scene. Apply a layer mask to the shadow layer. As before, use the Brush tool with black as the color to paint the mask, confining the shadow to the areas of the hand and chair where it will be seen. The final result is now two people soaking up the breeze where before there was only one.
Content-Aware Fill has been a life-saver for easily removing unwanted wires and the like; however, it’s not always perfect. A little planning and Auto-Align Layers can do a better job here, too.
step one: Here are two images side by side. When I took the shot I was going after the tree and its shadow. I didn’t want the traffic sign. In anticipation of having to remove the sign, I took three steps to the left and took the shot again. Compare the position of the sign in the two images. In the left image, the sign covers the juncture where the two tree branches meet. On the right, the sign is off to the right exposing the juncture.
step two: Auto-Align the two images. As with the image of the two chairs, apply a mask to the top layer. By painting into the mask over the area of the sign, you’ll make it disappear as if by magic! This image shows the sign being eliminated, exposing the detailed wall below.
There are so many features in Photoshop. No tool, filter, or any other feature of Photoshop is limited to the name it has been given. A change in mode here, a lowered opacity there, or the slightest alteration anywhere can totally change the function of the tool you’re using to suit your needs. As you just saw, the Auto-Align Layers feature was used for two opposing tasks. All you need to do is sit there and explore!