Ross & Ormsby, the Petaluma, Calif., photography studio, was a partnership of George Ross (1832-1893) and E. D. Ormsby, The launch of Petaluma (Calif.)'s Ross & Ormsby photograph studio announced in the Petaluma Weekly Argus on May 27, 1869:"A new firm in photograph in Petaluma. George Ross has entered into partnership with E. D. Ormsby, operator from Bradley & Rufolson's celebrated gallery in San Francisco. They are prepared to do every style of work known to the art. Enameled cards--new style. Call and see these beautiful sun pearls! Now is the time to have your wives' and sweethearts' picture taken on your watch dial!. At Ross' old gallery, Petaluma, May 20, 1868 [that is, 1869]. Ross & Ormsby." No mention of the photography studio can be found in local papers after 1870, though the partnership may have continued into the 1870s.

George Ross, ambrotypist and photographer, was born Feb. 2, 1832 in Edinburgh Scotland; grew up in New Orleans, followed the Gold Rush to California in 1849, and settled in Petaluma, California in 1855, where he lived for the remainder of his life until his death in early 1893. Ross worked as a painter between the time he arrived in Petaluma in 1855 at age 23 and the beginning of his his profession as a photographer in 1862. He moved his studio within the city several times as noted on his various cdv imprints prior to entering into partnership with E. D. Ormsby. in 1869. Their gallery was located on Main Street in Petaluma. and operated until at least 1870. He continued his photography work on his own, with a gallery at 36 Main Street, until his death. Ross was buried in Cypress Hill Memorial Park in Petaluma. (Palmquist, pgs. 461-463; Mautz, pg. 136).

E. D. (Elon Delamore) Ormsby was born in Michigan in 1846, and was active as a photographer in the San Francisco Bay area and Petaluma area between 1869 and 1884.He was still living in San Francisco in 1869, at 23, at 323 Minna and working at Bradley & Rufolson's gallery, the studio of Henry W. Bradley and William Henry Rufolson, located at 429 Montgomery Street, 1863-1869. That same year, he joined Ross as a partner in Ross & Ormsby. By 1878, he was living in Oakland on Chester and operating his own studio at 1166 Broadway (located in 1880 at 941 Market Street in San Francisco and from 1881 to at least 1888 at 1055 Broadway, Oakland). Ormsby died in Oakland of of heart disease at age 49 on March 6, 1895.