According to Thompson's son Lange got some details of this story wrong but the impact of the picture was based on the image showing the strength and need of migrant workers. Her index finger was left untouched (lower right in photo). She was informally apprenticed to several New York photography studios including that of the famed Arnold Genthe.
Dorothea Lange (May 26 1895 – October 11 1965) was an influential American documentary photographer and photojournalist best known for her Depression-era work for the Farm Security Administration (FSA). Lange's photographs humanized the consequences of the Great Depression and influenced the development of documentary photography.