In Chicago style, an image requires a caption with a footnote or endnote and an entry in the Bibliography.
An image caption provides information about the image and a footnote or endnote that credits the source of the image. Give each image a figure number (Fig. 1, Fig. 2, etc.).
If the image is a drawing, rendering, infographic, or other illustration, include:
If the image is a photograph of a building, include:
If the image is a photograph or reproduction of a work of art, include:
If you don’t see all of this information in the caption of the image or the text around it, look for a separate list of image credits. This list is often called List of Illustrations, Illustration Credits, Image Credits, or simply Credits. In books, it may be either at the beginning or at the end of the book.
Note: Museums rarely credit an individual photographer. You can cite the museum as the corporate creator of the photograph.
At the end of the caption, insert a footnote or endnote citing the book, website or other source where you found the image. Here's an example: