One of the most common uses of the GIMP is to fix digital camera images
that for some reason are less than perfect. Maybe the image is
overexposed or underexposed; maybe rotated a bit; maybe out of focus:
these are all common problems for which GIMP has good tools. The purpose
of this chapter is to give you an overview of those tools and the
situations in which they are useful. You will not find detailed
tutorials here: in most cases it is easier to learn how to use the tools
by experimenting with them than by reading about them. (Also, each tool
is described more thoroughly in the Help section devoted to it.) You
will also not find anything in this chapter about the multitude of
"special effects" that you can apply to an image using GIMP. You should
be familiar with basic GIMP concepts before reading this chapter, but
you certainly don't need to be an expert–if you are, you probably know
most of this anyway. And don't hesitate to experiment: GIMP's powerful
"undo" system allows you to recover from almost any mistake with a
simple Ctrl-Z.
Most commonly the things that you want to do to clean up an imperfect
photo are of four types: improving the composition; improving the
colors; improving the sharpness; and removing artifacts or other
undesirable elements of the image.