Make a Photoshop duotone.
How to make a Photoshop duotone for book printing on press. Self-publishers and designers can create them for print production for offset printing press. Print a black and white photography book with a different visual impact.
You see in the images in the feature image above, that the photo on the top is in color. The photo on the bottom is the same image, but converted to a duotone. The duotone is an image printed in black plus one other Pantone Matching System (PMS) ink.
Image format in 8-bit PSD, TIF or JPG, but not in 16-bit
Images or photographs can be in a .psd, .tif or .jpg format. In Adobe InDesign, you can link to the image file that has been converted to a duotone.
We say that a logo or another image is in full 4-color process, also known as CMYK. If already using a duotone of black plus one PMS, the color image will automatically make book printing a 5-color job. That changes the quote and increases the cost. Instead of 2-color printing for duotones, black (K) plus the selected Pantone ink) it will become 4-color process CMYK plus the 1 Pantone ink.
Start with 8-bit images. It is the standard and what we recommend, not 16-bit images.
Set-up for duotones
- Convert to Grayscale by going to Image > Mode > Grayscale.
- Once converted to Grayscale, you have the option in the same menu to select Image > Mode > Duotone.
- A new Duotone Options dialog box will open. Under Type, select Duotone. Then select the two inks you want to use.
Most often, the first ink is black. Make sure it is the black from the correct color library, Pantone Solid Coated for coated paper, or Pantone Solid Uncoated for uncoated paper. Be careful which color library you select.
These libraries do not designate paper stock to be gloss or matte. Before you select the library, either check the final book printing quote or contact your printer to verify paper selection.
Very Important: Choose process black, which is 100 percent black (K=100).
To select the second duotone ink, click on the box on the right. For the photo in our sample image, we selected Pantone 279 C.
If you want to save this Preset, simply click on the little wheel to the right of the preset that now says “Custom”. Give it a new name if you wish, and your duotone set-up will always be there for you. This is especially useful if you are doing the entire book in one duotone Pantone Matching System (PMS) color plus Process Black.
If the final image seems a little dark as compared to the grayscale original, two suggestions follow.
You can 1) select a lighter secondary ink or 2) create a curve setting. You will be able to adjust each image with an individualized curve setting. Read more about curve settings at Adobe Photoshop help.
When working with a duotone, or any image, be sure to understand resolution and effective resolution.