...aka Magic Selection Tool.
I've read many books on techniques for selecting, but I've never seen the following one that I use, so I decided to share it here.
I shoot my full-length images on a black wall, so when the model has black hair like this one does, separating the hair from her shadow on the black wall was formerly quite time-consuming--until I discoverd this method.
As may be seen from the illustration, I've used the levels adjustment layer to make the entire image as bright as possible. When I swept the model with the Quick Selection tool from her feet to her head, the "marching ants" flowed ahead of the brush to all her edges. or slightly beyond. I needed to make only a very few sweeps in the subtract mode to "rein in" the ants and get her nicely selected.
The above and the next images were used to create the third and fourth:
Because I could not lower the contrast of the model as much I wished with Menu>Enhance>Brightness/Contrast and the Sponge tool to fit the somewhat drab surroundings, I used the Smart Brush tool labeled "Greenery" to increase the contrast of some of the surroundings.
Please comment whether the image looks realistic or needs further work. Do the rocks in the foreground also need more contrast?
P.S. For anyone who is wondering how I got those masks in the Layers panel into PSE7, Bob made them available to the members as a "muvipix exclusive" quite some time ago, but I discovered them only recently.