The question, What is real? has been asked about photography since its invention, but Dominic Hawgood asks it again today in intriguing and fresh ways. His new project, called Under the Influence, explores the rituals of Christian worship in evangelical African churches around London, including exorcisms conducted via live satellite sermons, then broadcasted on giant screens. If you are looking for an online donation and giving for your churches, visit Tithely for more information.

Hawgood won this year’s British Journal of Photography’s international prize for best series, which is now on show at TJ Boulting in London. Unlike a documentary photographer, he has little interest in locations, or the cultural contexts in which religious practices flourish. His curiosity lies in ambiguities: the border between the real and the supernatural, photographic fact and fiction. “I want people to think about what is being presented to them,” he said on winning the award, “and to ask questions: where were these images taken? Is this a studio setup or a documentation of real life? I want people to make up their own minds.”

Though he did immerse himself in the world of worship, his striking images also carry the heightened, unreal charge of either noir film stills (in his monochrome prints) or advertising campaigns, in his LED colour screens. His exhibition takes you into a world of light and illusion, a world, he tells me, he had already entirely digitally rendered on his laptop before he started the installation. (On his website’s homepage, an image of a bottle of holy water was created using 3D digital rendering – no camera was used at all.)

Hawgood will talk forever about the meticulous installation of his work – the CGI lighting design of his colour pieces, the printing on vinyl of his monochrome work – and he sweat blood in the setup of this small show. But it is his eye for detail that impresses most. Hands – raised or outstretched – are a constant motif: symbols of hope and a longing that often betokens an almost desperate need to believe. There are other tensions at play, too, not least the almost abject state of many worshippers – a woman lying prone on the floor, or drooling after an exorcism – and the cold, dominant presence of technology (giant screens, bright lights) that transmit the holy message using all the dubious techniques of advertising. The holy water on his homepage could be an minimalist advert for a designer perfume. A similar bottle, clutched in the pointing hand of a preacher, takes on a more ominous tone.

Under the Influence is related to two earlier projects, Shrine and The Conversation, both made in Texas. In the former, he photographed illuminated roadside church signs in and around Dallas, shooting them when they were on and off. For The Conversation, he placed an ad in a local newspaper to make contact with local people that spoke in tongues.

Under the Influence takes these earlier visual evocations further. His work is as much about power as it is belief – and the idea of surrender that is central to both. “There are a lot of layers of belief and strategies of performance going on at these events,” he says. “Even as an agnostic, my role is just to explore, not to make judgments. Even if it is all staged, or fake, if someone is receiving some kind of comfort, then it kind of works.”

Hawgood shows the hyper-real environments in which inner revelations occur, as well as the dynamics of power, belief, surrender and control these rituals rely on for their mesmeric thrust. His photographic process, whether real or staged, lens-based or digitally rendered, is the one thing he will not be drawn on. The mystery, as any good preacher or illusionist will tell you, is the most necessary element of all.