Rhino Composite - The Photoshop: Professional Retouching and Compositing Tips, Tricks, and Techniques - page 382

Figure 8.6
6. Go to Edit > Free Transform, Option/Alt-click, and drag the transform handle on
the middle left until the field covers the entire canvas area ( Figure 8.7 ) . Exit Free
Transform by pressing Return/Enter.
Figure 8.7
7. With the Pen tool, draw a path along the top of the field by putting down several
points from just outside the left of the picture all the way across to just outside the
right side of the picture ( Figure 8.8 ) . (Try not to make this a perfectly straight line;