If the image you use is discussed within your paper or presentation, the image should have a caption. The caption is similar to an in-text reference and provides the information needed to lead your audience to the entry on your works cited list. Label the image with an abbreviation of 'Figure:' (Fig.) followed by a number and a title.
Below is an example of captioning a photograph, with the full citation in the "Image citation" box.
Fig 1. Liebowitz, Annie, Monument Valley, 1993.