When adding a photo to a story, you must populate the Photo Credit field and you can choose Alt Text and a Caption of your liking.
When Uploading A Photo From Your Computer
Once you choose a photo, the Add Photo dialog will appear. Credit, Alt Text and a Caption must be added in the respective text boxes. Link is optional.
When Adding A Photo From Our Image Libraries
When adding from our libraries, photo credits, alt text, and photo captions will frequently be set automatically from the catalog. If the information in those fields aren't relevant to your story, edit the photo credits, alt text, and photo caption fields.
To change them:
Click Edit Image in the photo options menu.
The photo dialog will appear and the existing caption can be changed.
Click Save to confirm the updated fields.