Bring Cool Colors to A Photo

In this tutorial we will learn how to play with colors in a photo, turn it into a cool and dark style that can easily impressive your viewers

Let's start to Photoshop!
Step 1: Download the original photo and open it with Photoshop. First we should make it darker by going to Image>Adjustments>Levels and drag the black slider to the right to make the photo darker

Step 2: Duplicate the photo by pressing Ctrl-J. We will make the photo more contrastive by turning this layer to black and white for later effects. Go to Image>Adjustments>Hue/Saturation and use these settings:

This will make our layer become nearly black and white

Step 3: One again using the Levels tool(Image>Adjustments>Levels) to make our photo darker by moving the black slider to the right. You can also make slight adjustments to other sliders

Step 4: Change the blending mode of this layer to Screen, notice that this mode just lets light colors go through. Our photo now looks brighter and more contrastive 

Step 5: Create a new layer and change foreground color to #1F768C (dark blue) and background color to #62bdd3 (light blue) and go to Filter>Render>Clouds to add random clouds to this layer

Step 6: Change the blending mode of this layer to Overlay to apply this layer's colors to the below layers

Step 7: Press Ctrl-Alt-Shift-E to create a new layer that is the result of all underneath layers. We will make lighting effect on this layer by going to Filter>Render>Lighting Effects and adjust the ellipse to create a light source from the top-left

Step 8: Our photo now looks great. This step is just optional to give the viewers a dreamy feeling.
Duplicate the current layer (Ctrl-J) and go to Filter>Blur>Gaussian Blur and use a small radius

Step 9: Now change the blending mode of this layer to Soft Light to make the photo a bit "softer"

Step 10: You can easily change the brightness and contrast of the photo by Curves tool (Image>Adjustments>Curves) or Brightness/Contrast tool(Image>Adjustments>Brightness/Contrast)

Let's have a look at the result again to feel the difference:

In conclusion, we used some blending mode (Screen, Overlay, Soft Light) with adjustment tools (Curves, Hue/Saturation, Brightness & Contrast...) and Lighting Effects to greatly change the colors of a photo, making it cooler and darker. Maybe you have seen some photos of this style!

http://www.9tuts.com/Photoshop/Photo-Retouch/Bring-Cool-Colors-to-A-Photo.html