This portrait is generally accepted to be one of the very few portraits of the photographer.
On "The Stereoviews of Carlton Watkins" (www.carletonwatkins.org) [Accessed: 21 Jan 2011] it has the following note about this photograph:
What is the story behind the photograph? As Jim Crain points out, Watkins' daughter Julia recalled that although her father did not like to have his picture taken, he did pose here as a miner, for his children. It was taken the same year that his son, Collis, was born.