Making a Fake Channel Split in Photoshop or Easy transparency

So this is a quick tutorial on how to make a transparent layer of shadows from a photo in photoshop, and as an added bonus we’ll be turning our photo into a faux channel split mis-registration piece (simulating a mis-registered plate during the four-color CMYK printing process).

So first, we’ll open our image in photoshop.

Just an image I had laying around.

If your photo isn’t black and white, you’ll want to go to Image > Adjustments > Black and White… to open the black and white filter dialogue.

The black and white filter dialogue

If you don’t care about your contrast, then you can just click auto and press OK. If you do, feel free to make your image as contrast-y as your heart desires by converting the tones of your image to shades of black.

After that’s done, you’ll want to select the entire canvas by pressing cmd + a or ctrl + a on windows (from here on out just replace cmd with ctrl if you’re on a PC). After that’s done, we’ll copy all of the canvas’ contents into our clipboard by pressing cmd + c. Then switch over to your channels panel in your layer window and click the add channel button in the bottom right (the little piece of paper icon next to the trashcan)

After you add the channel it should be black

Then, we’ll select the Alpha 1 channel we just made, and paste the contents we copied into the alpha channel using cmd + v.

After you paste the contents into the channel, it should look the same as the others. Then make sure to click the word RGB to switch back to your RGB channels.

After you paste the contents into the channel, it should look the same as the others. Then we’ll click the RGB channel to switch back to our current channels. (hint: make sure to click the word RGB or the space to the left of it and not the little eyeball or else you’ll solo that channel and things will get weird.) [also don’t forget to do this step or things will be REALLY weird.]

After you’ve switched back to your RGB channels, flip back into your layers panel and make a new empty layer by clicking the new layer button in the bottom of your layers palette.

With the new layer selected, head over to select > load selection… to open the load selection view.

Once we’re in the load selection view, we’re going to select alpha 1 from the channels dropdown. Then check the invert box to invert the selection so it selects the all the black pixels of our image.

Check yoself before you wreck yoself

Then we’ll press okay, and you should have some crazy selection that looks like this sorta.

So now, with our new layer still selected, we’ll select a round brush that’s hard, and really big. (Using the brush tool, press the b key. Then head up to the little brush icon in your top toolbar.)

Once you have a brush, and your opacity set to 100%, just click and drag a single layer of black over your image (Don’t click multiple times. Click once, drag a big wiggle over the entirety of your image, and then release. Better yet, you could use the paint bucket tool to do this in one click.).

It won’t look much different, but you should notice the black over the original image.

From here, we’ll right-click (or opt + click, weirdo) the layer we just brushed and turn it into a smart object.

Now our layer is compartmentalized into it’s own being and can be stretched without fear of weird raster things happening to it (unless you make it really big).

So then we’ll make a couple copies of that layer with cmd + j.

and then, for each layer, we’ll double-click to bring up the layer options panel, and apply a color overlay set to multiply on it. I’m going for a CMYK appearance, so I’m going to make one layer cyan, another magenta, and the third yellow.

Then, you’ll select all your layers, and set their blending mode to multiply. then set their fill values to 0%.

Afterwards, your canvas should look pretty much the same as you started, just a lot darker. Now, we’ll create a layer of white by creating a white rectangle and moving it behind all three layers.

Afterwards, select each layer and move it with the move tool (v) to mis-register it. It’s more subtle if you use the nudge movements with your arrow keys for small movements, however, subtle actions can also look unintentional.

and there you have it!

EDIT: If you’re a real efficiency nerd like I am, made an Action for making the transparencies. Link below.

https://www.dropbox.com/s/opb0wpg5lgvofgt/makealpha_action.zip?dl=0

Some appendix thoughts:

There’s no need to use a color overlay if you’re looking to do a single color layer (instead of our three layer mix). Once you’re ready to fill in your selection with color, you could simply choose the final color you want your layer to be and fill the selection with that instead of black. Then you’ll have a smart object that’s ready to go as the color you’re using.

This technique is actually insanely useful for making screen-printing stencils for photo-emulsion exposure.