In 1976, Gratz was asked to work for
Will Vinton in the new up and coming Will Vinton Studios, During her time at Vinton Studios, Gratz worked on many films as an animator, but in 1987 she decided to work as a freelance animator and filmmaker due to issues involved with collaborative film projects, and not receiving the proper credit for her work. Once a freelance animator and filmmaker, Gratz continued to be represented by Vinton Studio, In 1990, Gratz animated a commercial for
United Airlines entitled
Natural, which consisted of her clay painting technique. After eight years of planning and researching, and two years of working through the creation and animation process, Gratz completed her film
Mona Lisa Descending a Staircase in 1992. The title of this seven minute long film combines the titles of
Leonardo DaVinci's famous painting, the
Mona Lisa (1503), and
Marcel Duchamp's iconic modernist piece,
Nude Descending a Staircase, No. 2 (1919). beginning with
Impressionism, and continuing until the
Pop Art movement and
Hyperrealism Joan C. Gratz is featured as one of six interviewees in Martin Cooper's feature documentary
History, Mystery & Odyssey: The Lives and Work of Six Portland Animators (2023). The other interviewees are
Joanna Priestley,
Chel White,
Jim Blashfield,
Rose Bond and Zak Margolis. The film premiered at the 2023
Ottawa International Animation Festival. == Accolades==