This is the image I chose to use to edit on Photoshop.

 

 On this image I wanted to create a cross processings, retro effect. I did this by changing the curves and levels. I began by opening a new layer and going new adjustment, and curves. I changed the curves on the red, blue and green. I made an S shape for the blue and red, then I slightly altered the green. I then made a new layer and made it a colour layer, I used a yellow colour and changed the opacity to about 13%, this then added to the retro effect.