It’s hard to imagine a time when Pink Floyd’s Dark Side of the Moon didn’t exist. Its imagery has become so diluted into popular culture that it’s easy to forget its actual value as a rock & roll artifact.

Most of all, it stands as a beacon for an era of record cover design that we’ll never come into contact with again. Partly because artists and musicians have moved on to some other way to connect art and music, and partly because no label is going to hand over fifty grand for the artwork of the packaging if they don’t have to.

While any designer could probably have retired for the rest of their careers following the Dark Side cover, the thing is, it was just one in a number of celebrated sleeves designed by art house collective, Hipgnosis.

Hipgnosis was a trio made up of Storm Thorgerson, Aubrey Powell, and Peter Christopherson. Disbanding in the 80s, Thorgerson continued to work on record covers until his death in 2013, and Christopherson, who was a member of Throbbing Gristle, died in 2010. Powell now directs films, including Monty Python’s latest, Monty Python Live (Mostly). At the time, Powell and Thorgeson shared a flat with Pink Floyd’s Syd Barrett. Barrett inspired the name of the collective after he wrote “hipgnosis” on their front door. “Hip” referring to cool as a subculture, “gnostic” to organized religion, and “hypnosis” for the “artificially induced trance state resembling sleep characterised by heightened susceptibility to suggestion.”

From 1967 to 1982, they created cover art for Led Zeppelin, 10cc’s, Def Leppard, AC/DC, Scorpions, Paul McCartney & Wings, Genesis, Peter Gabriel, ELO, T.Rex, Yes, Black Sabbath, and many more, along with several other Pink Floyd covers. “Every Christmas we’d put all the artwork we’d done the whole year around the walls of the studio. It was extraordinary the output, what we’d managed to achieve between us,” says Aubrey Powell, speaking to me from London.

He describes the 15-year partnership as “very much like Andy Warhol’s studio in New York, where everybody pitched in,” whether that be coming up with ideas, or shooting scenes, and the vitality they shared as “extraordinary”.

“Storm had a young son, who he took care of and he generally stayed in England most of the time while I mostly spent my time out of England, photographing various ideas that we’d come up with Peter Christopherson,” he says.

“When we worked in England together and at the studio, the volume of work was so great during the 1970s that we couldn’t spend time designing at the same time as actually doing the physical work of photography. In those days, photoshop didn’t exist, and so our work was very much a very tactile business, very hands on.

“We used to meet very late at night. Probably two or three nights a week, til four in the morning sometimes, when we’d sit up and have design sessions — very much brainstorming sessions to try and create different ideas. We were very much in a lateral thinking kind of way, and often they were at Storm’s apartment and his apartment was always full of the most loose and loaded cannons you can imagine: there would be the guy in the corner throwing knives at a wall; there’d be a couple of Japanese groupies, drug dealers, all sorts of people and other designers, and it used to become free-for-alls. Probably Storm or I would come up with the initial idea for something and then other people would start throwing in ideas. It was hectic to say the least. At the very end it was always the same three of us left, and we’d hone it down to some succinct idea that made sense and would work, but it was a very free-for-all kind of atmosphere in those thinking sessions.”

It feels clichéd to reference Almost Famous in an article about 70s record covers. But the scene where William Miller flicks through his sister’s records in quiet awe paints a pretty good picture of how you imagine records and their sleeves were treated by music fans back then.

As Powell said in an interview several years ago, “In those days album covers were very important to the person who bought them because there wasn’t MTV, there weren’t music videos, and there wasn’t the saturation of YouTube or any other available source to learn about your favorite rock & roll star… You’d buy an album and scour the cover while playing it, looking for clues as to what made those artists tick.”

Before the 70s, most covers were just portraits of the artist or band, but as music became more abstract so did its cover art. In his book Classic Album Covers of the 1970s, Powell describes it as “the most important shot the artist had at getting across his self-image.”

And Hipgnosis’ style and designs were what these artists wanted. “The surreal photo designs that Hipgnosis produced were without any doubt what drew bands to us,” Powell tells me. “It was the salad days of album cover design… We could do what we wanted. We never took a brief from a band who told us what to do. We very rarely put photographs of the band on the front cover. We were almost always more interested in the design and what the design meant, and to make a design that was stimulating and interesting and enigmatic in some way.”