Tips for writing an effective caption include matching the caption to the tone of the rest of the text, avoiding replicating content, and including appropriate citations and credits. Photos and captions should complement each other and tell the reader something intriguing that the picture does not say.
Caption copy must match the tone of the associated text and, therefore, can be formal, informal, serious or funny. Captions should be in present tense with short, snappy sentences that describe when and where the action in a photo took place without stating the obvious. The caption should intrigue a reader enough to make the reader want to learn something new and read the story.
Effective captions should not begin with names and should name people only if they are important to the picture. If names are used, the names should be spelled correctly, and people should be identified from left to right of the photo.
A caption should allude to associated text content while not repeating it. This means that captions should be unique, should be based on facts, and should not contain content that is already directly in the text elsewhere. Captions should also include credits, written in a consistent style and format, to acknowledge the photographer or source material.