My Cross-Processing Technique

Since posting my cross-processed Subway picture on Flickr and my web site, RAILhead Design, I've been receiving dozens of emails per hour asking about my process. So, I thought it only appropriate this Holiday Season to share the basics of how I do cross-processing. But first, let's get some "history" out of the way so we're all on the same page.

When I say "cross-processing," what I'm referring to is the process of chemically developing film — and doing so with the "wrong" chemicals. Without getting into all the details, negative film is processed with E6 chemistry and print film uses C41 chemistry. In cross-processing, you simply switch the chemicals for the film, and the result is an image with Lord knows what kind of coloring, texture, or contrast. This technique gives images that "edgy" and "gritty" — over color exposed, if you will — look.

Now that more and more photographers are moving into the digital realm, we have to find ways to mimic things like cross-processing via software — and that software is Adobe Photoshop. More specifically, I'll be using one of Photoshop's most potent image manipulation tools: Curves. I must also say that there's no real "scientific" or hard-and-fast rules to get a good cross-processed image. The desired look will be different for different people, and the source image will sometimes require different settings than those you'll see here — but the foundation principals are the same.

All that fluff aside, below you see the source image and the final image, side by side. Notice how the final (bottom image) has a lot more contrast and colors are almost blown. There's also a bit of a green hue to the whole image, and it looks quite "destructed":




Now that you know where we're heading, let's get one more thing out of the way: adjustment layers. If you plan on doing much image post-processing, I highly recommend you get into the habit of using Photoshop's Adjustment Layer capability. By doing this, you not only maintain the integrity of the source layer, you maintain the ability to adjust and readjust the layers you add — as well as turn their visibility on and off to see how they effect the source image. Also, it's not a bad idea to duplicate your master layer just to be safe.

So, open your source image and go to Layer > New Adjustment Layer > Curves and clock OK in the dialog box that appears. You can also click the New Adjustment/Fill Layer button (the black and white circle) at the bottom of the Layers palette.

From the Channel popup menu, select the Red channel. An image's red channel is lots of fun when it comes to tweaking shadows and highlights, and that's what we're going to do here. First, though, I always anchor the mid-tones by setting an anchor point in the center. I then deepen the shadows by placing and anchor at input 64 and moving it vertically until I *just* get a smooth curve. I then blow the highs a bit by placing an anchor at the top, about input 190, and drop it vertically until I get a smooth curve. Below you see my Curves window and the before and after (source on top, modified on bottom).





Now select the Green channel from the popup menu and we can start making this image look nice and nasty. I start by dropping the highs so things get a bit muddy, somewhere about input 255, output 208. I then set another anchor at input 190 with the same output to really flatten the highs. Next I drop an anchor about input 97 and output 128, which increases the mids to get things a bit nastier. Lastly, I drop an anchor to bring out shadows at input 64, dragging it vertically until it makes a nice, smooth curve. Below you see my Curves window and the before and after (source on top, modified on bottom).





The last channel to modify is the Blue channel, so select that and we'll fine-tune all the metal surfaces and lights. On this channel, I start by placing an anchor to blow the highs a bit, somewhere around input 190, and dropping vertically to get a smooth curve from the upper right. Next I set the shadows much like I did on the red channel, about input 64 and vertical to get a smooth curve. As for the mid-tones, I stick to input 128 and move vertically to really give the metal a nice bluish tint. Too much blue looks like blue — and we want this to be somewhat subtle. And, depending upon how much metal (or any other reflective surface) you have in your source, just increase or decrease the output to get a feel you like. Below you see my Curves window and the before and after (source on top, modified on bottom).





And that, my friends, is a painfully simple way to get a decent representation of a cross-processed image. You can ramp-up the colors by increasing the image's saturation if you want, but I rarely do that myself.

The basic foundation for this process is to deepen the shadows and blow the highs — and since I'm partial to making CP images look sickly green and yellow, I ramp the green channel as described above.

So fire up your copy of Photoshop and set things like I have here — and since you're using Adjustment Layers, you can go back and tweak each channel to your liking. Once you have your basic settings figured out, you can make yourself a Photoshop action that does it all for you, too.

One last tip I forgot to mention previously: sometimes you can get a good effect if you flatten all the modified layers, leaving the original untouched, and set the merged modified layer to the Overlay blending mode.

Enjoy!