"So I started experimenting and got into wet plate. And at that stage I was certainly the only one in New Zealand that did it, and even 20 years after that there was just nobody."
Mr Scadden said there were only eight people in the world practising the art when he started, "now there are thousands".
He said the rise in popularity of the art is the result of people wanting to regain control of the craft "in the age of modern technology and digital photography".
"In the early days or even 10-15 years ago, you would go into your darkroom and print black and white prints," he said. "Even that is really just gone basically. I think people just really want to feel that they are in charge of something, that they have actually made the photograph themselves.
"I wouldn't have a clue how my phone takes a photograph, and I think that's the crux of it - people worldwide are starting to think well wouldn't it be great to actually get hands-on and go back to grassroots."
Mr Scadden's partner, Jane Fletcher, has more than 30 years of photography experience and first started working with wet plate at Mr Scadden's workshop over a year ago.
Ms Fletcher, who fell in love with the process, said it was different to contemporary photography because imperfections in wet plate are embraced rather than dismissed.
"I like to think of it as the imperfect beauty of the plate," she said.
"Because we get taught now, photographically, that everything has to be perfect, perfect light, perfect composition, perfect everything, and to do this, it's a complete flip of that thinking and I much prefer this way.
"It is more natural, you know. There's a depth and a warmth to the process that you just can't replicate on digital, even film."
"As the image never fades, it becomes a treasured family heirloom. People get a real buzz watching their image appear; kids especially, as they have never seen anything like it."
Ms Fletcher said the process, which takes about 20 minutes, is "beautiful" because every time a photo is created it is "completely unique".
"You'll never ever get two plates the same, even if you are doing a still life, because the light will have changed just a fraction, or your pour will be different."
Mr Scadden and Ms Fletcher's business, Brass & Glass Photographic Alchemy, will be at the Martinborough Spring Vintage Fair October 17 and featured at Wai Art during the Daffodil Festival where they photographed Carterton Mayor John Booth.