In my last post, I demonstrated how effective and attractive can a two spot colour print be. Today, I want to share some behind-the-scenes of achieving similar result in a quick and easy tutorial.
Choosing colours
Let’s say our project is a tropical destination postcard and it will contain a photograph of a nice sandy beach.
Original full colour stock image
Great! But what colours to use if we are limited to only two Pantones? By looking at the image we can definitely decide that one of the colours will be blue. Not too dark, as its tints would be more grey-ish than blue (Pantone Tints guide comes handy), and not too light as it will be the colour of body copy that needs to be legible, i.e. in good contrast to background. Our second colour will be a yellow for two reasons: we need to reproduce colour of the sand, and yellow mixed with blue produces green! So we get another colour for free — a rather nice result of subtractive colour mixing in print.
Full colour gamut of Pantone 2995 and 1215
Getting the image right, step-by-step
1. Let’s load our original image into Photoshop.
2. From menu Image/Mode choose Multichannel. In Channel window (Window/Channel) you should see three channels named Cyan, Magenta, Yellow. In Multichannel mode you can add/remove channels, so let’s remove Magenta, leaving only the other two (as they are the most similar to our target spots). You will see the image changed appearance.
3. Double click the Cyan channel and in Spot Channel Options dialog click on the Color swatch. A familiar colour dialog will appear. Press Color Libraries button and choose Pantone Solid Coated. Let’s choose Pantone 2995C. And for our Yellow channel choose Pantone 1215C. You should see new channel names.
4. Now we need to adjust the channel’s contrast a bit so the image doesn’t look so washed out. Choose the blue channel only (by leaving only this channel switched on — you’ll see it in greyscale) and try to darken the sky and water to almost black with Levels or Curves. In contrast, adjust the sand area to near white. Now choose the yellow channel and adjust the image that the water and sand are nearly black in appearance and the sky is almost white.
Channel adjustments in Photoshop
5. Make both channels visible and you should get something like this:
Finalised image
6. Save it as Photoshop DCS with .eps extension, leaving the default options intact.
7. Place the image in InDesign and notice that two new colours appeared in Swatches window. Delete all other swatches to be sure you’re using only two spot colours for the project.
That’s done! Now you can export your finished postcard to PDF and if you’re printing with PrintHouse Corporation, don’t forget to use our PDF/X preset, which you can download from here.
