Cross-processing (also known as “xpro”) is the procedure of deliberately processing film in a chemical solution intended for a different type of film. As the chemical mixture is optimized for a special kind of film, you will get unpredictable results when combined differently.
Before anything else, let us brief you on the different chemicals used for some of the common types of film that we use:
- Color negative film (also known as “negatives”) uses C-41 chemicals for processing. You get negatives as a result to these.
- Color reversal film (also known as “slide film” or “transparency” film) uses E-6 chemicals for processing. You get “slides” as a result of these. Think of slides as the slides that your grandparents used for slide projectors (hence the word “slideshow”) to bore everyone with their photos from their last trip.
Now comes the fun part. When you cross-process, you use the chemicals for color negative film with color reversal films, and vice-versa.
- If you process negative film thru the slide chemicals (E-6), you will get slides. Although the colors will not be as wacky; you will just get a kind of slide film with no big color shifts.
- If you process slide film in the negative chemicals (C-41), you will get negative film, but with the Lomographic burst of colors! This is because the color layers of the film were not optimized for this. As a result, the photos turn out saturated or grainy or with high contrast and you get all kinds of unexpected results. Different films have different characteristics when cross-processed. Some turn out more yellow or more green while others turn purple or red.
There are other ways for cross-processing but the most popular one used in Lomography is processing your slide film with C-41 chemicals.
Also remember that everything depends on how you process your film. The chemicals, the machine calibrations and the developing process (the order, the temperature, etc.) are responsible for what you get towards the end. When you have your film processed, you get different results from different labs because they do not always use the same chemicals and calibrations.
New to Lomography and want to learn about Cross processing? Check out our guide dedicated to x-pro photography at http://crossprocessing.info/
To know more about the different films Lomography.com has to offer, visit the Lomography Online Film Shop.