After dissolving his previous partnership, he established himself in a photographic studio at 116 Sauchiehall Street during 1857. In 1859, the business moved to 200 Hope Street and he was also able to establish a printing works in Hamilton in 1863. First interested largely in architectural photography and then portraits, as well as photographing artworks and maps, in 1866 Annan photographed slum areas of the city. These images were used by Glasgow City Improvement Trust to document the overcrowded, unhygienic conditions ahead of extensive redevelopments. It was this series of photographs, created between 1868 and 1871, entitled Old Closes and Streets of Glasgow, that ensured his posterity.
In 1869, Annan purchased the contents of Rock House, which belonged David Octavius Hill, which included many of Hill's photographs and negatives. These were eventually exhibited by Thomas' son, James Craig Annan, and reproduced in photogravure in Alfred Stieglitz's journal Camera Work.
Annan's photographs of the Loch Katrine Waterworks were praised in the British Journal of Photography: "The views by Mr. Annan could scarcely fail to be attractive, for in a country so beautiful a clever artist is bound to produce results in keeping with the nature of the subject, and this Mr. Annan has done." Indeed, Annan's work was often praised not only for its aesthetics, but also for its technical virtuosity. Twenty years later, Annan's studio would be singled out by Baden Pritchard for its accomplishments in carbon printing and "beautiful pictures of exteriors and interiors of Scotch strongholds."
Thomas Annan purchased the rights to the photogravure process in Britain from Karel Klíč of Vienna in 1883 after visiting the city with his second son, James Craig Annan. James was a noted photogravurist and associated with late nineteenth-century art photography continued in his father's profession, receiving a Royal Warrant as Photographers and Photographic Engravers to Her Majesty in Glasgow.
Thomas Annan died on 14 December 1887 at his home in Lenzie. Before his death by suicide, he had experienced a month-long period of "mental aberration". The family business survives to the present day in the form of the Annan Fine Art Gallery, located on Woodlands Road in the West End of Glasgow. A selection of prints from the Glasgow Improvements act 1868 series were displayed in the Scottish National Portrait Gallery from 2011 to 2012. In 2017, the J. Paul Getty Museum curated an exhibition entitled Thomas Annan: Photographer of Glasgow, the first to survey his career and legacy as photographer and printer.
Sources: Wikipedia
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