Most professors of art history require that you use of the Chicago citation style to create bibliographies and footnotes. There is also a variant of Chicago known as the Turabian citation style that is used as well. Because citations direct your reader back to the work of scholarship you are using in your research, they will differ slightly depending on the type of research material you are working with. For example, an article in a book will include information about the publisher of the book, while an article in a journal will include the name of the journal and its volume and issue number. It is best to include as much information about the resources you are working with as possible so anyone who wishes to look at those resources will be able to find them.
The Chicago Manual of Style Online is the venerable, time-tested guide to style, usage, and grammar in an accessible online format. It is the indispensable reference for writers, editors, proofreaders, indexers, copywriters, designers, and publishers, informing the editorial canon with sound, definitive advice.
Image captions should include both the location of the work itself (if relevant), as well as the location of where you found the image. Below is an example of a mass produced image made available through a digital collection and how you would cite it depending on where you found the image.
Title: Silence = Death
Artist: ACT UP
Date: 1987
Medium: Color Lithograph
Location of work: Widely available
Fig. 1. ACT UP, Silence = Death, 1987. Color lithograph. Museum of Modern Art.
Fig. 1. ACT UP, Silence = Death, 1987. Color lithograph. Wikimedia Commons. https://commons.wikimedia.org.
Fig. 1. ACT UP, Silence = Death, 1987. Color lithograph. AIDS Demo Graphics. By Douglas Crimp and Adam Rolstan. Seattle: Bay Press, 1990: 30.
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