Des Haut Des Bas

Cross-processing is the procedure of deliberately processing one type of film in a chemical solution intended for another type of film. There's something extremely charming about a photo that's cross-processed. Of course it's possible to cross-process without actual chemicals and with Photoshop. 

1) Select the image you want to cross process and load it into PS. 

2) Add a curves layer by going to Layers > New Adjustment Layer > Curves OR just click "Create New Fill or Adjustment Layer." 

3) Select the red channel and adjust it so it looks like an S shape.

4) Next, select the green channel and raise the right part of the curve and slightly lower the left part. 

5) Next is the blue channel. It should resemble an inverted S shape. 

6) You can then adjust the RBG channel to increase contrast. 

7) Voila. Save your picture! 

You can decide how big or small you want the curves to be to get the colors of your liking. 

Before Cross

After Cross