Tough Guy - The Photoshop: Professional Retouching and Compositing Tips, Tricks, and Techniques - page 365

Tip
You can check to see if you missed any areas by Option/Alt-clicking the layer
mask in the Layers panel. Then simply paint in black or white to fill in any gaps.
To return to the normal view, Option/Alt-click the layer mask again ( Figure
7.10 ) .
Figure 7.10
6. Now we're going to add a vignette. With the Elliptical Marquee tool, drag out an
ellipse in the center of the picture. Then add a Levels adjustment layer and move
the midtones point to the right to darken it ( Figures 7.11 and 7.12 ).