Photo Caption Method
This option allows you to show the photo caption from the Single Image element in VC. When you add the image, enter the artist’s name in the photo caption section of the image you select from the media library. Then check the box in the VC element to show the caption (screenshots below, you can click them to make them bigger).
Custom Heading Element Method
This method allows you to use a preset of the Custom Heading element to add captions if you would like more flexibility in placement. You just add a Custom Heading, click on the gear at the top of the box, click view presets and select Photo Credit. All the necessary option will be filled in for you. All you have to do is change the text.