Here are 2 short Videos replicating depth in preparation for my final project: https://www.artstation.com/community/projects/8l21GE/edit
The boulder is made from 2 separate images. I adjusted the colours and use simple planes to create the illusion of depth.
The ruins is made from a single image which was more challenging as I had to make sure the backgrounds were filled in.
I made the mistake of shifting the camera before the render, resulting in showing part of the background not painted in.