[kencaleno]

You only need one jpeg:

Graduated Neutral Density Filter effect

Add adjustment layer> levels
Drag right slider to left
Drag middle slider to left (These moves enable you to get the foreground how you want it-don't worry about the sky blowing out-it will be fixed with the next action))
Press “D” or "X" to make foreground color black
Press “G” for gradient
Choose linear gradient -black to transparent-2nd icon from left
Drag cursor from top of image down to horizon
flatten/save

Regards, Ken