When backdrop painters were successful at their jobs, the filmgoing audience didn’t notice their work at all. From the 1930s, up to the emergence of CGI and higher quality photography, painted backings were an essential part of the cinema industry. However, the artists were barely credited, no matter how important their transformation of reality was to a film — whether a colossal painting that transported the viewer to an exotic locale or a fantastic mural for an entirely fictional realm.

The Art of the Hollywood Backdrop by Karen L. Maness and Richard M. Isackes, out now from Regan Arts, is a visual compendium of over 300 images highlighting this unheralded history.

“These special effect backings, the largest paintings ever created, were breathtaking in their artistic and technical virtuosity,” the authors write. They note that although the “majority of backings used today are digitally printed photographic enlargements,” the painted backdrop still remains a part of film, albeit in a reduced role:

But, paradoxically, the painted image often looks more realistic than the photographic image. Scenic artists can manipulate backings by adjusting light, color, and texture, helping to support the movie camera’s constructed image. Some information and details can be selectively accentuated, while others can be deemphasized. A photograph, on the other hand, is static and has a tendency to contradict the artifice of the rest of the setting.

They also point out how recent films, like 2004’s Lemony Snicket’s A Series of Unfortunate Events and 2014’s Interstellar, also incorporated painted backings to instill an otherworldly atmosphere. Most of the book is concentrated on artists who made significant contributions to the “golden age” of Hollywood. Before the 1930s, films were often staged like theater, backgrounds not intended to be viewed as anything other than flat space. Then emerged films like 1936’s The Petrified Forest. Shot entirely at the Warner Bros studio in Burbank, California, all its scenes were set in the Arizona desert, with realistic backdrops integral to moving the action, even if the actors didn’t go anywhere.

You probably haven’t heard the backdrop artists’ names — although Salvador Dalí makes a brief appearance with his dream sequence backing for the 1945 Alfred Hitchcock film Spellbound. You’ve almost certainly seen their work, even if your brain perceived it as a real three-dimensional space, such as George Gibson’s scenic art for the Wizard of Oz or North by Northwest, and Ben Carré’s artwork for classics like The Phantom of the Opera. No matter the place, the painted backdrop was crucial to the audience’s immersion in the cinematic world.

The Art of the Hollywood Backdrop by Karen L. Maness and Richard M. Isackes is out now from Regan Arts.