Wild Montana: 4 Exposure in 1 Photo
The "new school" method is to take multiple exposures and then blend them together manually in photoshop.
There is also another method, which I'd call the "school dropout" method which uses an HDR program to create an automatic blend of these photos which the computer finds beautiful. I own the most up-to-date HDR program and it does not create natural-looking shots.
So, for this shot, I used the "new school" photoshop blending, relying heavily on the lightest shot to give this work a gorgeous luminance.