A zombie thread was revived on TOS silverware. Rather than feeding the zombie, I figured I would respond to something Zap said concerning the color of the Enterprise model.
I can't believe Jeffries thought it should be blue when he knew they had to shoot the model in front of a blue screen.
Perhaps it was known that the VFX crew worked only with bluescreen. However, that was far from the only "traveling matte extraction" technique at the time. To make a "composite" shot, such as a ship in space, one must make more than a single exposure—hence the name composite. However, a common double exposure will result in ghosting effects. Any bright areas in the background, like stars or a planet, will expose over the same area as the ship.
"Mattes" are like those mask templates used by road crews when spray-painting a "STOP" sign on pavement. By using both "positive" and "negative" mattes of a foreground subject (like a ship), a "double exposure" can be made without the ghostly see-through problem. The ship photo is exposed through the ship-shaped mask onto a new piece of film. That film is then rewound and exposed a second time for the background. Only this time the area of the ship is masked by a ship-shaped silhouette.
The first "traveling mattes" were made by hand, tracing a subject frame-by-frame with rotoscope, a technique invented by Max Fleischer (who made the early Popeye cartoons). Bluescreen was a later "automatic traveling matte" technique, but it was not the only one. Disney used the sodium vapor lamp system to make the composites in Mary Poppins. While those extracted mattes are very clean and do not have the limitation of avoiding a background color in foreground subjects, they are more expensive. (They need the special lamps, and a double camera for the normal film and sodium sensitive film.)
And there are many other techniques. 2001: A Space Odyssey used reflex front projection for the "Dawn of Man" sequence, a variant of which was used later in the Christopher Reeve Superman movies. 2001 also used "model mover" multiple exposures for the Discovery in space shots—which is extremely time consuming because of the long exposures used. The camera/model movement was also limited due to the pre-computer, mechanical mover equipment. But 2001 has some of the cleanest composites in film history. (No generation loss from copying a copy of a copy of a piece of film.) The VFX crew for Spaceballs used an upgraded version of this model-mover approach. Models were moved in a blacked-out studio for the first pass. A second pass, moving camera and models the exact same way, was then made under UV light. Since the models had all been coated with a UV-reactant lacquer, they "lit up" and produced bright silhouettes of themselves. One advantage of this technique is that even fine details, like the "rabbit-ear" TV antenna on Lonestar One, will show up in the composite.
Bluescreen became so popular because common film stocks could be used. The hard part was all done in the lab. Blue exposed through a red filter makes "black," and the negative of red exposed through a blue filter also produces "black." And that is how the lithographic, deep black mattes were extracted from common film. But all those exposures produce grainy "generation loss."
Film and television engineer Petro Vlahos invented Ultimatte in the 1970s, the first high quality electronic compositor for video. And as cinema quality digital cameras arrived, the common blue background shifted to green for technical reasons. Although any color can be used. Digital compositing has also solved the motion blur problem, added features like "lightwrap" and other subtleties to make modern composites completely undetectable. It is even possible in realtime with a Webcam to extract a common background, as anyone who has used Zoom or chat filters knows.
We've come a long way.
I can't believe Jeffries thought it should be blue when he knew they had to shoot the model in front of a blue screen.
Perhaps it was known that the VFX crew worked only with bluescreen. However, that was far from the only "traveling matte extraction" technique at the time. To make a "composite" shot, such as a ship in space, one must make more than a single exposure—hence the name composite. However, a common double exposure will result in ghosting effects. Any bright areas in the background, like stars or a planet, will expose over the same area as the ship.
"Mattes" are like those mask templates used by road crews when spray-painting a "STOP" sign on pavement. By using both "positive" and "negative" mattes of a foreground subject (like a ship), a "double exposure" can be made without the ghostly see-through problem. The ship photo is exposed through the ship-shaped mask onto a new piece of film. That film is then rewound and exposed a second time for the background. Only this time the area of the ship is masked by a ship-shaped silhouette.
The first "traveling mattes" were made by hand, tracing a subject frame-by-frame with rotoscope, a technique invented by Max Fleischer (who made the early Popeye cartoons). Bluescreen was a later "automatic traveling matte" technique, but it was not the only one. Disney used the sodium vapor lamp system to make the composites in Mary Poppins. While those extracted mattes are very clean and do not have the limitation of avoiding a background color in foreground subjects, they are more expensive. (They need the special lamps, and a double camera for the normal film and sodium sensitive film.)
And there are many other techniques. 2001: A Space Odyssey used reflex front projection for the "Dawn of Man" sequence, a variant of which was used later in the Christopher Reeve Superman movies. 2001 also used "model mover" multiple exposures for the Discovery in space shots—which is extremely time consuming because of the long exposures used. The camera/model movement was also limited due to the pre-computer, mechanical mover equipment. But 2001 has some of the cleanest composites in film history. (No generation loss from copying a copy of a copy of a piece of film.) The VFX crew for Spaceballs used an upgraded version of this model-mover approach. Models were moved in a blacked-out studio for the first pass. A second pass, moving camera and models the exact same way, was then made under UV light. Since the models had all been coated with a UV-reactant lacquer, they "lit up" and produced bright silhouettes of themselves. One advantage of this technique is that even fine details, like the "rabbit-ear" TV antenna on Lonestar One, will show up in the composite.
Bluescreen became so popular because common film stocks could be used. The hard part was all done in the lab. Blue exposed through a red filter makes "black," and the negative of red exposed through a blue filter also produces "black." And that is how the lithographic, deep black mattes were extracted from common film. But all those exposures produce grainy "generation loss."
Film and television engineer Petro Vlahos invented Ultimatte in the 1970s, the first high quality electronic compositor for video. And as cinema quality digital cameras arrived, the common blue background shifted to green for technical reasons. Although any color can be used. Digital compositing has also solved the motion blur problem, added features like "lightwrap" and other subtleties to make modern composites completely undetectable. It is even possible in realtime with a Webcam to extract a common background, as anyone who has used Zoom or chat filters knows.
We've come a long way.
Last edited:
