From telescopes to satellite cameras to electron microscopes, scientists are producing more images than they can manually inspect. This tutorial will introduce image analysis using the idea that "images are just NumPy arrays". Then we will run through various fundamental image analysis operations (filters, morphology, segmentation), and finally we will demonstrate one or two advanced real-world examples. This tutorial is aimed at people who are familiar with NumPy, SciPy, and Matplotlib, but it does not require any previous knowledge of image analysis or image processing.