In 2018 Sellen won the UK round of the Amateur Photographer/EISA Maestro competition with a street photography portfolio, then placed second among thirteen countries at the EISA Maestro Awards, presented at a gala in Berlin.² In 2019 his image Out of the Glow won the black-and-white category of the Fujiholics Photographer of the Year competition, with finalists' work shown at the Hull International Photography Festival.³

His limited-edition prints have been sold through Treacle Art Gallery, and in 2019 he launched The Limited Ten, a monthly release of prints limited to ten copies each.^4,5 His photographs have also been shown alongside work by photographers including Reuben Wu and Ryan Koopmans in MONOLITH Gallery's virtual exhibition halls.⁶