Having said that you should avoid using mirrors to create reflections, here’s one way you can do it with a single image and without sacrificing reality—unless that’s what you want to do, of course.
- Open an image of a reflective object. A car’s rearview mirror is a good choice, and it’s easy enough to go out and shoot one if you don’t have anything else to work with.
- Convert the background layer of the image into a regular layer by double-clicking it and clicking OK in the resulting dialog box.
- Open an image with a scene that you want to show reflected in the mirror. Drag the image layer from this image onto the image with the mirror in it. Then close the second image.
- When you look at objects through a mirror, they’re reversed, so you should flip any image that has text (street signs, for instance) that will look wrong otherwise. Click the layer that you want to flip, and choose Edit > Transform > Flip Horizontal. Hide this new layer for now by clicking its Layer Visibility icon.
- Click the bottom layer to make it active. Make a selection around the area where the second image should appear inside the mirror. Feather the selection a little by choosing Select > Feather and applying a small feather value to soften the edge. With this selection in place, click the Layer Visibility icon for the topmost layer so it’s visible again.
- Click the Add Layer Mask icon at the foot of the Layer palette. Immediately, a layer mask will be created that automatically places the image inside the mirror.
- Notice that the layer mask is a black-and-white image. Where the image is black, that part of the image is hidden; where it’s white, that part of the image is visible. A final touch is to darken the inside edge of the mirror as it was in the original image (see Figure 5).
Figure 5 This simple reflection is created by placing a scene inside a reflective object, such as a car mirror.