How to colorize highlights and shadows of a photo

Question

How is it possible to achieve the effect created in this photo:

Any help is much appreciated!

Answer 1

1. Select orange as background colour
2. Select blue as foreground colour
3. Select from the menu Image->Adjustments->Gradient Map. Unfold the drop-down and make sure the first gradient option is selected (from foreground to background).

Note: You might want to do some prep work first and exaggerate the contrast by playing with the levels. It might help turning the image grayscale first.