He likely switched from glass plates to film negatives around 1915. None of these have survived. On October 22, 1935, on his annual autumn journey from Mackinac to Daytona, William H. Gardiner died of a heart attack. The studio and shop on the second floor of the Fenton Building on Mackinac Island remained property of the family until Louise and Marshall Gardiner's deaths in 1942, within days of each other. The contents of the studio were abandoned where they remained in an unused portion of the second floor for the next quarter century. William H. Gardiner and Louise were survived by their son H. Marshall Gardiner and his sister. H. Marshall Gardiner became a famous photographer in Nantucket, MA.