painting (action)
When a character in the image is shown engaged in the action of painting (verb).
For images depicting a scene that includes a piece of artwork, i.e. an actual painting (noun), such as on canvas, or framed on a wall, use painting_(object) instead.
For images that are actually painted by the artist (e.g. post #2013647), see traditional_media instead. Please refrain from using this tag if this is the case.
For images depicting a painting on someone's body, use bodypaint instead, unless the image shows a character currently/recently engaged in the act of painting on the body (such as paintbrush in hand).