Images can include a title and caption which can come from any of 8 different sources:
- Text Custom Title
- Text Custom Caption
- Attributes Title Text
- Attributes Alternative Text
- Attachment Title Text
- Attachment Alternative Text
- Attachment Caption
- Attachment Description
When Title Text or Alternative Text are selected as the source, values from the Attributes toggle will be used first. If no values are found there, values will always be taken from the media attachment.
See here for positioning the text.
See here for styling the title.
See here for styling the caption.