Photographs of immediate family, including photograph of young Thomson, c1890s; photograph of Hector and classmates at his Officers' Training Corps academy, c1930s; photograph of Lady Thomson and her sister in academic dress, 1904; photograph of Lady Thomson with 2 companions in a small rowing boat, 1905; photographs of plays acted at Armstrong College, many of which Lady Thomson took part in, c1900s; formal photographic portrait of Thomson's Father, Charles, 1939, as well as a photograph of Charles sitting in a garden, c1910s; and formal photographic portraits of Lady Thomson's Mother and Sister, c1900s.

There are also photographs of ancestors, and more distant relatives, some with contextual information inscribed, as well as photographs of places meaningful to the Thomson family. These include a sepia photograph of Thomson's Great Grandfather, Andrew, c1890s; and photographs of family members from the Dickinson and Oates lines; photograph of the house in Moorside, 1925; photograph of the Physikalisches Institut in Strasbourg, c1920s; and photograph of Glenapp, c1940s.

Also includes papers relating to the photographs such as handwritten family trees detailing the Thomson side; notes by Thomson's relative, Margaret Thomson, regarding his Father and Uncle; and notes regarding letters sent by Thomson's Kendal and Canadian sides of the family.