For these exercises, feel free to utilize the images on this book’s website (http://the-book-ofgimp.blogspot.com).
Exercise 7.1. One simple tool we did not use in this chapter is Image: Colors > Threshold. Try using it on a poor-quality image. Experiment with the placement of the cursors. Try to remove noise and to emphasize the important parts of the image.
Exercise 7.2. Because the Threshold tool generates a black and white image, combine its result with the initial image in a different layer. Try various merging modes until you feel that you’ve increased the amount of information that a researcher could extract from your image.
Exercise 7.3. Try using the image generated by the Threshold tool to fill a layer mask added to the original ...