Unlike most investigations of Loch Ness, Gerard Byrne’s new show is not at all interested in the existence of a monster. His first major solo exhibition in a UK public space is about Nessie as a photographic phenomenon rather than a flesh and bone saurian.

Speaking via phone, the Dublin-based artist explains that what piqued his interest in the place was its relation to the history of photography. “As a site it amounted to a kind of cardinal point, you might say, in the way of people’s expectations of photographs, people’s beliefs in photography as such,” he says. “Do you know what I mean?”

Byrne has a knack of firing this short question back throughout the interview, usually after making one of his more abstract points. It is a worry because he asks it like he expects an answer.

“Now, I’m not a puritan or a fetishist or anything like that but I’m interested in the idea of photographs as a type of material as well, as a type of material that’s generated through certain processes – both optical and chemical – and so it sort of matters that they’re analogue prints [in the show] and it sort of matters that they’ve been generated through this, you know, physical temporal commitment to that site, if you know what I mean.”

By way of comment on the many famous pictures which claim to show what may or may not be in the local waters, Byrne has spent 10 years making a collection of his own photos of Loch Ness.

“There are people who’ve actually lived in caravans up there and camped out. I haven’t done that. But I’ve made a lot of visits at least – I’d say at least a dozen visits, each for, like, a few days at a time, so I’ve put in some time up there,” he says.

And as you might expect from a visual artist, Byrne sets the scene very well. “Firstly the loch is very, very big,” he says. “It’s much bigger than you might imagine. It’s quite epic in scale and it’s actually not the most beautiful part of the Highlands, the most, you know, windswept or romantic.”

To the ears of an ignorant southerner this is almost disappointing, until he adds: “It is a little bit dark you might say. I don’t want to be melodramatic, but it is a little bit dour and dark in comparison with the surrounding landscape…it’s sort of sombre, you might say.”

Byrne’s engagement with this figurative scenery was not without its ironies. “I go there and I make a lot of photographs and I look at the photographs after the fact and I realise that they’re all landscape photographs,” says the conceptual artist.

“There’s a type of topography at work in the photographs,” he says. “But in the end what they really chronicle is, I think, an idea of forms which could be mistaken for other forms.”

In other words there’s a now-you-see-it-now-you-don’t quality to the work on display, monsters at which you have to look twice.

“That’s one of the ideas that’s very visible when you see the show – you know, this idea of the gestalt form, this idea of something that’s almost in the mind’s eye,” he adds.

It is, after all, such gestalt forms which give rise to lake-dwelling monsters. “That’s a kind of archeptypal myth that’s found all around the world, and what distinguishes Loch Ness from the rest is precisely its mediation in the newspaper,” says Byrne.

He goes on to explain that interest in Loch Ness peaked in the early 1930s, at a time when the mass media was becoming all pervasive and more people were becoming aware of a sense of modernity.

“It’s interesting that there’s so much attraction to a myth that’s primarily about the primeval, that’s about the idea of something from prehistory, that could continue to live in the 20th century or the 21st century,” he says. “So there’s a strange fantasy built into that that’s about time or about escaping time or something that defies time.”

In which case new town Milton Keynes is the last place you’d expect to find a mythical dinosaur. But now that is where you will find it, as large as life – an indisputable phenomena if nothing else.