Jumping in late into this discussion, but hoping some of this furthers your research a bit.
Ranikhet and Bareilly were (and still are) garrison towns in colonial India. They are located 110 miles apart, so the Magnet Studios were probably two branches under common ownership.
I don't find any records of Joseph Byron Clayton or kin moving to India, so were the Indian Magnet Studios bonafide franchises or not? Doesn't really matter, but it does look like someone leveraging upon the brand back home. As philipsearching noted, Joseph Byron Clayton opened Magnet Studio in Leicester in 1873 (see
http://freepages.genealogy.rootsweb.ancestry.com/~brett/photos/eng/ntt/wclayton.html) so the Magnet studios in India must have come after it. If true, this rules out Andrew Minto who died in 1858. This leaves John Alexander Sutherland (b. 1878, left for Africa in 1890s) in the frame. The subject in your photo could be 18-22 years old, which would tie in with this.