Moses Billings
With the development of the daguerreotype in the 1840s, the role of the portrait painter declined in general, because it was now much easier and much cheaper to have one's likeness presented in a visual format. While many portrait painters lost business in competition with the daguerreotype, Billings instead began to produce daguerreotype prints himself. It is not known exactly which prints were made by Moses Billings, as daguerreotypes were usually signed, when signed at all, along the side of the plate. Due to the traditional storing methods of daguerreotype plates, even this signature usually quickly became illegible. However, it has been generally noted, or at least hypothesized, that his daguerreotype prints showed a level of talent and artistry above that of amateur daguerreotypists. Though it is not known exactly which prints were his, it is known that he had largely abandoned the process by the 1850s. Even after he stopped making daguerreotypes, he did continue to paint people's portraits on canvas.
Robert Cornelius
With his own knowledge of chemistry and metallurgy, as well as the help of chemist Paul Beck Goddard, Cornelius attempted to perfect the daguerreotype. Around October 1839, at age thirty, Cornelius took a self-portrait outside of the family store. The daguerreotype produced is an off-center portrait of a man with crossed arms and tousled hair. While Daguerre's photograph of the Boulevard du Temple, taken one year earlier, has since been discovered to incidentally include two human figures on the sidewalk (they just happened to stay motionless long enough to imprint on the exposure), Cornelius' image – which required him to sit motionless for 10 to 15 minutes – is the oldest known intentional photographic portrait/self-portrait of a human.