The Amazing High-Tech Drawings that Made Star Wars Possible

Long before anybody had seen a single frame of Star Wars, these luminous drawings were all anybody could see of George Lucas' vision for a thrilling space epic. These "dyelines" were created to show possible backers and studio executives something tangible.

The science behind the creation of these brilliant prints is almost as exciting as what they reveal about the early versions of some Star Wars icons like the Millennium Falcon and Han Solo.

These images were drawn mostly, if not entirely, by Lucas protégé Joe Johnston, whom Lucas would later convince to go to USC film school. Johnston worked on all three of the original Star Wars trilogy films, starting out as an illustrator on A New Hope and moving to Art Director for Empire Strikes Back and Return of the Jedi. Johnston would go on to direct Rocketeer, Jumanji, and this summer's Captain America: The First Avenger.

The Chemistry behind the Dyelines

These dyelines were produced by exposing the original Joe Johnson vellum drawing to ultraviolet light while the drawing was laid over UV sensitive diazo paper. Diazo paper is coated in a reactive diazonium salt. A diazonium salt is an organic compound with two linked nitrogen atoms as a terminal functional group, and the salt forms are often found with a chloride conjugating the terminal nitrogen atoms.

After the master drawing and diazo paper are exposed to ultraviolet light, the sections of the diazo paper left exposed to ultraviolet light are chemically inactive. These exposed portions retained the original color of the diazo paper. In the next step of the process, the diazo paper is exposed to ammonium hydroxide, a weak base which can cause poisoning in humans. The reaction between the diazonium salt and the ammonium hydroxide caused the unexposed sections of the diazo paper, those shielded in the previous step by the master drawing, to become visible.

In the case of the Star Wars dyelines, these unexposed sections became blue, and mirrored Johnston's original drawings. This was a rather expensive way to create a print, but it produced a very high quality, detailed image that could be used by others in the prop department to create intricate models and miniatures. More common copies of the dyelines were later created, with these being in black and white. They are often called "cactus prints" amongst Star Wars collectors due to common cactus logo on the back of the print.

A Peak into the Early Story of Star Wars

These dyelines are particularly interesting, as they reveal the visual origins of Star Wars. In several dyelines, what would later become the Millennium Falcon is a "pirate ship" that looks something like a Rebel Blockade Runner. Also, the character who would later become Han Solo is always shown with a helmet covering his face.

These dyelines are wonderful, physical pieces of Star Wars history that cannot be changed by interviews or time — they stand on their own. Around 10-15 copies of each dyeline were made, with many damaged during a flood at Elstree Studios. As several of each print exist (and the dyelines themselves were replaced with black and white copies later in the production of Star Wars as the technology became more available), a handful have found their way into the collector's market. These dyelines have to be kept out of ultraviolet light to this day, as markings left on the diazo paper can still fade.

It doesn't get much more geek cool than hanging a piece of art that helped get Star Wars financed on your wall. The dyeline shown above is from the collection of Leif G.

Check out more of these amazing illustrations in our gallery.


Images courtesy of Lucasfilm.

The Amazing High-Tech Drawings that Made Star Wars PossibleS

A dyeline of the main gun of what would become the Millennium Falcon, sold in a Christie's UK auction in 2009.

The Amazing High-Tech Drawings that Made Star Wars PossibleS

A dyeline showing the positioning of a gunman in what would be the main turret of of the Millennium Falcon, sold in a Christie's UK auction in 2009.

The Amazing High-Tech Drawings that Made Star Wars PossibleS

Joe Johnston at work designing in front of a wall of reproduced dyelines. Cinefex, March 1996 issue.

The Amazing High-Tech Drawings that Made Star Wars PossibleS

A dyeline hangs on a background wall during the construction of a Star Destroyer prop. Cinefex, March 1996 issue.

The Amazing High-Tech Drawings that Made Star Wars PossibleS

A dyeline showing an early version of the "pirate ship" and a helmed character that would become Han Solo.

The Amazing High-Tech Drawings that Made Star Wars PossibleS

Joe Johnston's Star Wars Sketchbook, Ballantine Books, 1977.

The Amazing High-Tech Drawings that Made Star Wars PossibleS

Reproduction of a tie fighter dyeline published in the Star Wars Sketchbook, Joe Johnston, Ballantine Books, 1977.

The Amazing High-Tech Drawings that Made Star Wars PossibleS

Top view of the Millennium Falcon. From a reproduction of a dyeline published in the Star Wars Sketchbook, Joe Johnston, Ballantine Books, 1977.

The Amazing High-Tech Drawings that Made Star Wars PossibleS

This is where the torpedo goes. From a reproduction of a dyeline published in the Star Wars Sketchbook, Joe Johnston, Ballantine Books, 1977.

The Amazing High-Tech Drawings that Made Star Wars PossibleS

A Rebel Blockade Runner dyeline from the collection of Leif G.

The Amazing High-Tech Drawings that Made Star Wars PossibleS

From a reproduction of a dyeline published in the Star Wars Sketchbook, Joe Johnston, Ballantine Books, 1977.

The Amazing High-Tech Drawings that Made Star Wars PossibleS

From a reproduction of a dyeline published in the Star Wars Sketchbook, Joe Johnston, Ballantine Books, 1977.

The Amazing High-Tech Drawings that Made Star Wars PossibleS

A dyeline showing the cockpit of the Millennium Falcon gun turret (yourprops.com).

The Amazing High-Tech Drawings that Made Star Wars PossibleS

A dyeline showing the arduous path through the Death Star trench (yourprops.com).