In the autumn of 1844, Augustus Washington left Dartmouth College and traveled to Hartford, Connecticut to take charge of one of that city's two schools for black students. Despite a meager salary, he succeeded in paying off his college debts and looked forward to one day resuming his own studies. But by the close of 1846, Washington had returned not to Dartmouth but to the practice of daguerreotypy.

On December 24, 1846, Washington advertised the services of his new daguerrean enterprise in the pages of Connecticut's antislavery newspaper, the Charter Oak. Several months later, Hartford's city directories carried the first listings identifying Washington as a daguerreotypist and documented the relocation of his studio from 9 Waverly Building to Kellogg's Building at 136 Main Street. While he was not the first to offer daguerreotype likenesses to the citizens of Hartford and its environs, Washington would outlast his early business rivals and in 1851 could point with pride to the longevity of his gallery noting, "This is the oldest Daguerrian [sic] Establishment in this city."

Washington sought the patronage of a broad range of customers by offering both competitive prices and an extensive selection of cases, frames, bracelets, lockets, and rings in which to house his "beautiful and correct miniatures. Surviving portraits from his Hartford studio illustrate his success; they range from images of the city's elite, sometimes housed in elegant silver-bordered cases, to those of men and women of more modest circumstances, whose likenesses were packaged more simply. Further testament to the popularity of Washington's gallery and the scope of his clientele can be found in the words of a contemporary, who observed, "Augustus Washington, an artist of fine taste and perception is numbered among the most successful Daguerreotypists in Hartford, Connecticut. His establishment is said to be visited daily by large numbers of the citizens of all classes." When Augustus Washington published a notice in the Hartford Daily Courant on March 29, 1853 announcing plans to close his gallery in a few months time, he gratefully acknowledged "the kind and liberal patronage of a discerning public [for] the last seven years." He would retire from business "not from any want of further success or patronage, but for the purpose of foreign travel, and to mingle in other scenes of activity and usefulness."