Cross processing (xpro) refers to processing film in a chemical solution intended for a different type of film (Wikipedia).
Two methods are common: processing color negative films in slide chemicals (“C-41 as E-6”), or processing slide films using the color negative chemicals (“E-6 as C-41”). Due to the characteristics of the films and chemicals, the effects are different. Processing color negative film in slide chemical tends to produce flat tones and muted colors with less red but more green/yellow while processing slide film in in color negative chemicals often produces very contrasty images with blown highlights. In either cases, we’d expect to see wild color shifts that are not quite predictable due to many factors such as film/chemical, exposure, etc, will affect the process.
Simulating the cross processing effect in photo editors are fairly easy using curves adjustments in individual color channels. For photoshop users, this is a nice tutorial on how to do the “C-41 as E-6” type cross-processing in Adobe Photoshop. For demonstration purposes, I will show you how to do the same adjustments using Nikon Capture NX2.
We start by opening a photo in Capture NX2, then open the Curves & Levels adjustment tool via Adjust->Light->Levels & Curves menu or using keyboard shortcut Ctrl-L (Windows).
Select individual Red, Green, and Blue channels and make adjustments as shown in the aforementioned Photoshop tutorial. The following screenshots show you what I got.
Go back to RGB channel, the curves will be shown as following. As suggested in the Photoshop tutorial, we leave the master RGB channel adjustment into a 2nd Levels & Curves adjustment.
As suggested, we change the opacity settings as below so the adjustments only affects the colors not the luminance. By doing so, the adjustments to color and the luminance is de-coupled, saving you some frustration going back-and-forth.
Add a new Levels & Curves adjustment step and adjust the RGB curve to get the desired contrast you’d like as shown below. Change the opacity setting so it only affects the luminance by dragging the Chrominance slider all the way to the left (zero).
Add a Colorize adjustment step as shown below. Use the color RGB=(225, 255, 0) and change the Opacity settings as shown for the same reason mentioned earlier.
This is the final Edit List with all items collapsed.
Here is a before and after comparison of an example image.
I also tried the adjustment on the example photo in the Photoshop tutorial and got similar results as shown there. The effect isn’t exactly the same but that’s not important. There is no set standard on how the cross-processed photos will look like.
If you want to keep the adjustments, you can select all edit steps in the Edit List, right-click, then choose Save Adjustments. You can then run batch processing on other photos, Copy/Paste, or Load the adjustments to other photos opened in Capture NX2.
For your convenience, I have attached my settings file below. Enjoy!
Keywords: C41, Capture NX, Capture NX2, Chemical, Cross Processing, E6, film, Nikon, tutorial, Tutorials, XP, XPRO