Even if you would preferably apply effects in your photo editing software, it's interesting to have such effects in Scribus when you need duotone documents or you want to use some custom and precise colors on your image.
Let's go back to the
pict8-4.tif
file that has some clearly identified colors.Display the Image Effects window using the way you like most.
First select the Contrast and apply it by clicking on >>. It should appear in the right-hand column.
A slider is now visible under the preview: drag it to the right to increase the contrast as you wish.
Then choose the Grayscale effect and apply it. It should appear under the previous in the right-hand column. Grayscale has no parameter.
Then select the Duotone effect and apply it. For this duotone effect, you'll be able to set the color you want to use and the amount.
In the Color 1 list, choose Black, and just under it where 100% is written select 70% instead so that there is...