Bingo!
Lots of misalignment in the matte and foreground element, too. The ship shots improved in later seasons. It's amazing Trek survived its first season. It was such an unusual show.
Some great camera tricks
- Thread starter ZapBrannigan
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Lots of misalignment in the matte and foreground element, too. The ship shots improved in later seasons. It's amazing Trek survived its first season. It was such an unusual show.
If that "yikes!" is in regard to all the lab work needed to pull a traveling matte from bluescreen, I agree. In video, the technique is called chroma-key (or "colour separation overlay" in the UK). Basic chroma-key used the blue channel information to drive a switching circuit. If pixel is blue, go with background image. If pixel is not-blue, go with foreground image. This absolute either-or switching produced "non-linear" composites. That is, if the CK threshold was too low, slight variations in the blue background (say from shadows) would create unsightly, electronic "holes" in the image.
Then film and video engineer Petro Vlahos created the Ultimatte, I think the first digital, linear keyer for video. The circuitry of Ultimatte actually processed red and blue channels like the film process described up-thread. Even in the days of Standard Definition video, Ultimatte produced as near-perfect composites as one could ask for. The "linear" part means it could transfer shadows on the color background into the composited shot. (In the example below, note how Sagan's shadow carries over onto the Alexandrian Library background, which was a table-top model. The motion-tracking was achieved with selsyn-locked cameras, one on the full-scale blue stage, the other suspended over the model with a periscope.)
I forget the exact percentages now, but with NTSC (North American Standard Definition video), green made up over 50% of the signal, with red next, and blue making up the least portion. Thus, green became the favored color for color separation composites.
Today we have software that can distinguish background and foreground party from a "difference" comparison, and partly a face/person recognition routine. The difference method compares a stored image of the background with what the camera is currently seeing. If what the camera sees live (person) does not match the background, it is allowed through. A combination of this difference and Ai approach can be found in many virtual meeting packages, obviating the need for a green or blue background.
I don't think so. Some optical printers have metal blades in the gate, something like the blades of a lens aperture. They can be used for simple garbage mattes. But the "Armageddon" image posted by Zap is not a straight edge.
https://i.postimg.cc/ncx65r1r/Armageddon.jpg
Note the straight reference line under the lower hull. The edge of the hull is an irregular curve, and dips downward toward the stern where the hull tapers. Here the hull appears to dip down. I think that's the result of blue spill and the resulting matte as described up-thread. (I don't have the animation immediately at hand, as the version ripped into my media center has the digital FX for this episode. Since I do not have a Blu-ray player, I'd have to extract the original episode just to check this. But at the edge of the frame posted by Zap, the hull appears to widen at that point—as it would for the curve of the model, and catching blue spill.)
Also note the "notch" in the front of the saucer. I think that's another blue spill caught by the bevel of the saucer. The TOS VFX were loaded with matting errors like this. We know that VFX were a bottleneck in production. And the work was "good enough" for the television of the time.
That's a stock element used throughout the series and on the main titles starting in season two, where it looks mostly fine. The front edge of the saucer isn't even in shadow. If it were mere bluescreen spill, the problem would show up elsewhere.
Looking at the "Armageddon" shot in motion, the sensor dish is barely there on the side, and would get little to no bluescreen bounce. Looking at the video, I think the mattes are improperly exposed and not correctly aligned. Film shrinks and stretches, which makes perfect mattes difficult.
Looking at the "Armageddon" shot in motion, the sensor dish is barely there on the side, and would get little to no bluescreen bounce. Looking at the video, I think the mattes are improperly exposed and not correctly aligned. Film shrinks and stretches, which makes perfect mattes difficult.
I think it was originally filmed for WNMHGB. It has the nacelle spikes and the oversized main deflector dish. Here it is in "The Doomsday Machine":
The saucer notch is still there, the rest is different.
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