To whet your appetite and keep your writing fingers limber, take a good look at the photo, or let a prompt settle in your mind. Set a timer for a reasonable amount of time, be that five, fifteen, or thirty minutes. Then start writing.
Imagine that your character visits an art gallery where she can enter new worlds through the paintings. Where would she go? Would be able or want to return?
Look at an old portrait of a family member for a few minutes. Seek to see the person in a new way. Then record what you notice.
Write about how amateur photographers can take great pictures with their phones. Or write about how someone interested in drawing might get started.