Duotones & Tritones (Class 5)
Why Should I Print in Duotone (two colours) or Tritone (Three)?
A normal print is considered to be a 4 colour print. Since the offset printer uses one ‘plate’ to apply each colour at a time, (CMYK = 4 plates applied separately) as opposed to a two or three colour print job which can be considerably cheaper to produce. This means cost savings for you or your client, especially for high volume prints. Sometimes a magazine or brochure can have a 4 colour cover and a Duotone inside. Business cards and fliers may also be printed Duotone or Tritone to save money.
To create a Duotone or Tritone a series of steps need to be completed. First open you desired image in Photoshop
You will then need to Grayscale the image:
Image > Mode > Grayscale
Discard colour? Yes! (OK)
It’s important to have a lot of contrast in Grayscale/Duotone/Tritone images otherwise they tend to look muddy, to do this:
Image > Adjustments > Levels…
You can either grab and adjust the black slider arrow (on the left) and also adjust the white slider on the right
Or you can use the black eyedropper tool to select the blackest black in the document, and the white eyedropper to select the whitest white.
With these tools you should be able to get a nice striking contrast going before converting to Duotone.
When you are satisfied that there is enough contrast in the image, accept your changes (OK)
Next you will convert the image to a Duotone:
Image > mode duotone
Type (Dropdown) > Duotone
Black will show up automatically (C=0, M=0, Y=0, K=100%) you can either leave the black or select a different colour
To specify a second colour, click on the second colour
If the pantone colour swatches pop up and you want a Pantone colour, select one
(be sure to pick a pantone colour that goes with your paper type, ie if you’re using uncoated paper select pantone uncoated etc.)
For this purpose we going I chose Pantone solid Coated (as if I was printing on Coated paper)
You can also adjust the curves on the colour
Curves means how much ink coverage will be used. For example using an amount of 50% will lighten the amount of ink used by 50%
You can also save these as a preset if you need to apply the same Duotone to several images
If you don’t want a Pantone colour you can click on ‘Picker’ to change it to a CMYK value
Make sure to zero out the values that you don’t want in the CMYK section and to adjust the single colour value you DO want:
(also ignore the HSB, LAB, and RGB values)
Selecting only yellow means I will be adding only one additional printing plate to the black (2 Plate job is cheaper)
If you wanted a Tritone you’d select Tritone from the drop-down menu and choose either a third CMYK colour or a Pantone.
To save the file for export to InDesign:
File > Save As > (PDF) ‘filename-duotone.psd
(note that tiff also works, but only these two formats)
Bringing the file into Indesign & Mixing Shades of your Duotone/Tritone:
File > Place > (choose file)
When you import a Duotone or Tritone image into InDesign, the colours in the file will automatically be imported. You can see the new colours by opening the ‘Swatches’ Pallet. You can now use these colours to mix new (in between) shades from the colours you selected. It is very handy to have a selection of varying shades of a duotone or tritone to use creatively in your design.
To do this, in the swatches panel, click the swatches fly-out menu > new mixed ink (mixes a single ink)
(The flyout menu is the little black arrow at the top-right of the swatches pallet)
This opens the ‘New Colour Swatch’ Mixer dialog
Make sure to change the Colour Type to “Process” NOT SPOT, then drag the sliders or enter percentages of the two (or three) colours you chose to create an in-between shade. When you are happy with the mixture click “Add” and the swatch will be added to your swatches library. In the example here, I entered 100% yellow and 10% Black. You can repeat this process several times in the same dialog before exiting by hitting “OK.”
Alternatively InDesign can Create a full spectrum of Group Colours for you
To do this, make sure the swatches pallet is open, click the swatches flyout menu arrow at the top right of the pallet
Choose > New Mixed Ink Group
Set the initial value, set the repeat value and the increment value
In this example I’ll be starting with a value of 10% black, repeating 9 times, incrementing the colour by 10% each time. I’ve entered the same settings for the Pantone Yellow. You can click on ‘preview swatches’ to preview the results. In this case, I’ll end up 100 varying shades of black, grey and yellow to use in my design, that will still only using two printing plates.
You can click on preview swatches to see how many new swatches will be made.
Links to add to resources section: