He and his wife Adrienne co-founded Museum Technology Source in 1990 .
Callahan worked at Harvard University from 1977 until 1994 , at the Carpenter Center for Visual Arts .
Callahan and Callahan 's wife Adrienne co-founded Museum Technology Source in 1990 .
Callahan worked at Harvard University from 1977 until 1994 , at the Carpenter Center for Visual Arts .