Precise Background Swaps Using Photoshop and Perfect Mask
This article is the first of five that will introduce you to some of the suite’s new capabilities; here we’ll focus on the major update to Perfect Mask (Formerly Mask Pro). This plugin can be used for many purposes but one of the most common is swapping the background of one photo with that of another.
Preparing Your Pictures
Before we jump into details of Perfect Mask, you need to set the foundation for a good workflow. Assuming you shoot raw formats, that starts with Photoshop and Adobe Camera Raw (ACR). For this example, I chose two shots of a historic abbey in the United Kingdom. The first shot has an interesting composition, but the sky was partially blown out. Because HDR software tools were not as evolved back in 2006 and because I was pressed for time, I did not have bracketed exposures for this scene.
Fortunately, earlier the same day, I captured another shot at a different location, which had a similar, cleaner looking sky. The objective is to quickly swap out the sky in the first photo without harming the details of the abbey. First, open both of the images into ACR, and adjust their exposures, colors, and details (including Noise Reduction and Lens Correction) before opening them in Photoshop.
A useful tip: While you can use Perfect Mask’s tools to remove residual Chromatic Aberrations (or CA) after a mask is created, it’s generally quicker to take care of high contrast edges with color fringes in ACR. The processed raw files are shown in Figures 1 and 2.
Figure 1 The abbey composition and detail are fine, but the sky details are blown out in some areas and were not recoverable in ACR.
Figure 2 The sky in this shot is a good choice because of the similar light conditions and the fact that the subject locations will not interfere with the abbey in the other photo.
Once you are satisfied with the ACR edits, open both pictures into Photoshop. Here I did so in 16-bit mode using an Adobe RGB 1998 profile; this is one of the profiles you can set inside of the Perfect Photo Suite as a preference, along with ProPhoto RGB and others.
Next, click on the picture that has the content you wish to remove, hold down the Shift key, and with the Photoshop Move tool (V) drag it onto the image that contains your replacement content, then release. When you’re finished, you should (ideally) have two layers with the same dimensions, centered on the same coordinates, with the layer to be masked on top in the Layers panel (Figure 3). Here the transparency has been reduced to illustrate the positioning of the two subjects relative to one another.
Figure 3 Here you can see that the sky from the underlying shot is the only area that will overlap the masked area in the abbey photograph.