His main interest was landscape painting under the tutelage of Hendrik van de Sande Bakhuyzen.

[3] He remained at Vassar for the remainder of his life, living in a small house near the campus with occasional trips back to Europe.

Under his leadership the school grew from an initial curriculum of practical studio exercises to include studies of art history and criticism.

[2] Van Ingen was deeply influenced by The Hague School, a movement that emphasized traditional Dutch subjects such as interiors and landscapes.

He was described by one of his students as a "burly Dutchman reared within sound of Antwerp chimes - [He] has a homely, kindly face and very approachable manners, but stands no nonsense".