- Part 1 -
Chapter IV. FRONT PROJECTION
For the first time, front projection using a reflective screen was applied 4 years before Stanley Kubrick, in 1963, in the Japanese film Attack of the Mushroom People [4]. A long, conversational scene of a sailboat sailing on the sea was filmed in a pavilion, and the sea was projected onto a large screen in the background (Figure IV-1):
Figure IV-1. * Attack of the mushroom people *. The most general plan with the sea in the background. An image of the sea is projected onto a screen from an adhesive tape.
Since Attack of the Mushroom People has a very broad shot with a sailboat in the foreground and the sea in the background, you can calculate that the background screen was about 7 meters wide. When building a combined frame, the position of the camera is rigidly linked to the plane of the screen. The entire image projected onto the background is taken into the frame, and a small part of it is not used, since the image quality deteriorates greatly during framing, sharpness is lost and graininess increases. When it is necessary to change the close-up of the shot (Fig. IV-2), the apparatus remains in place, and the scenery with the actors moves closer or further, to the right or to the left - for this, the scenery is installed on a platform moving on wheels.
Figure IV-2. A still from the film "Attack of the Mushroom People", medium plan. The set with the sailboat was rolled closer to the camera.
When in 1965 S. Kubrik began filming "A Space Odyssey", he perfectly understood the tasks of state importance assigned to him. The main task is to create a TECHNOLOGY, with the help of which, by means of cinema, it is possible to achieve realistic shots of astronauts staying on the Moon, in order to then give these fake shots - combined shots - for the greatest achievement of mankind in the exploration of outer space. It took two years of painstaking work to develop such a technology (closed production cycle). According to the contract, the director had to deliver the final version of the film no later than October 20, 1966. But only by the middle of 1967 was it possible to close the chain of all the necessary working elements and create a technological procedure for the conveyor production of the so-called "lunar" frames. In the summer of 1966, work on "A Space Odyssey" came to a halt and for almost a year Kubrick tried to solve a single technical problem - projection onto a giant screen to create lunar landscapes.
Some parts of the technological chain had already been perfectly worked out long before Kubrick, for example, countertiping large-format materials. Some missing steps, such as taking photographs of a real lunar mountain to be projected onto the background, are about to be resolved by the robotic Surveyor stations sent to the moon. Some elements of the technological process had to be invented during the filming - for example, the projector had to be redesigned for large slides measuring 20 x 25 cm, since this did not exist. Certain elements had to be borrowed from the military - anti-aircraft searchlights to simulate the light of the Sun in the pavilion.
Promotional video:
Shooting of the film “2001. A Space Odyssey”is a cover operation where, under the guise of filming a fantastic film, a technology for falsifying“lunar”materials was developed. And as in any cover operation, the main cards should not be revealed.
In other words, the film should not contain frames that will then be “quoted” (fully reproduced) in the lunar Apolloniad missions. Please note: according to the plot of the film, in 2001, astronauts find themselves on the Moon, where they discover the same mysterious artifact in the form of a rectangular plate as on Earth. But the moon landing in the film takes place at night, in a bluish light hanging over the horizon of the Earth (Figure IV-3).
Figure IV-3. * 2001. A Space Odyssey *. The landing of astronauts on the moon takes place at night. Combined shot. In the background - a projection of the landscape from the slide.
And the landing of astronauts in the Apollo missions will, of course, take place during the day in the light of the sun. But Kubrick cannot shoot such a frame for the film, otherwise the whole secret will be revealed.
Nevertheless, the task of creating "lunar" shots remains the most urgent, for this the film was conceived. Such shots, when the actors in the pavilion are in the foreground, and a lunar mountain landscape is projected into the background, must be worked out in all the details. And Kubrick takes pictures like that. Only instead of a real lunar landscape, a very lunar-like, mountainous landscape of the Namibian desert in southwestern Africa is used, and animals are walking in the foreground instead of astronauts (Figure IV-4).
Figure IV-4. Shot from the prologue * At the dawn of humanity * for the film * 2001. A Space Odyssey *.
And this mountain landscape should be illuminated by a low sun with long shadows (Fig. IV-5), since, according to legend, the landing of astronauts on the moon should take place at the beginning of a lunar day, when the lunar surface has not yet had time to heat up to + 120 ° C, at the height of the sun above the horizon is 25-30 °.
Figure IV-5. The mountainous landscape of Namibia, illuminated by the low sun (image from the slide), is combined with the foreground props landscape in the pavilion of the MGM studio.
Figure IV-5. The mountainous landscape of Namibia, illuminated by the low sun (image from the slide), is combined with the foreground props landscape in the pavilion of the MGM studio.
![Figure IV-6. A slide (transparency) for a background projection measuring 8 x 10 inches (20 x 25 cm) [5]](https://i.greatplainsparanormal.com/images/003/image-8963-6-j.webp "Figure IV-6. A slide (transparency) for a background projection measuring 8 x 10 inches (20 x 25 cm) [5]")
Figure IV-6. A slide (transparency) for a background projection measuring 8 x 10 inches (20 x 25 cm) [5].
These slides were projected in the pavilion onto a giant screen 110 feet wide and 40 feet high (33.5 x 12 meters). Initially, Kubrick made the test samples with 4 "x 5" (10 x 12.5 cm) transparencies. The background image quality was good, but not perfect, so the choice was made for transparencies 4 times larger in size, 8 x 10 inches (20 x 25 cm). There was no projector at all for such large transparencies. Working closely with MGM's special effects supervisor Tom Howard, Kubrick set about building his own super-powerful projector.
In the projector, an intense burning arc with carbon electrodes was used as a light source, the current consumption was 225 amperes. Water cooling was provided. Between the slide and the electric arc there was a condenser - a block of collecting positive lenses about 45 cm thick and fire-resistant glass of the Pyrex type, withstanding temperatures up to +300 degrees. At least six of the rear condensers cracked during filming due to high temperatures or cold air entering the projector when the door was opened. The projector was turned on for a period of 1 to 5 minutes, only for the duration of the actual filming. With a longer arc burning time, the emulsion layer of the slide began to crack and peel off from temperature.
Since any dust or dirt appearing on the surface of the slide was magnified and visible on the giant screen, the most careful precautions were taken. Antistatic devices were used and transparencies were loaded under “antiseptic” conditions. The operator who loaded the plates into the projector wore thin white gloves and even wore a surgical mask to keep his breath from fogging up the mirror. [6]
Getting the combined frame looks like this. The light from the projector in which the overhead is installed hits the silver coated glass at a 45 ° angle to the projector axis. This is a translucent mirror, it is about 90 cm wide and is rigidly mounted on the projector bed 20 cm from the lens. In this case, 50% of the light passes through the mirror glass directly and is not used in any way, and the remaining 50% of the light is reflected at right angles and falls on the reflective film screen (Figure IV-7). In the figure, the outgoing rays are shown in yellow.
Figure IV-7. Obtaining a combined frame by the front projection method.
Glass balls of the screen return the rays back to their original point. In the figure, the return rays are indicated in red-orange. As you move away from the screen, they gather in a point, in focus, and their brightness increases greatly. And since there is a semitransparent mirror in the path of these rays, half of this light is deflected into the lens of the projector, and the other half of the returned light falls directly into the lens of the movie camera. To get a bright picture in the film channel of the shooting camera, the projector lens and the camera lens must be exactly at the same distance from the translucent mirror, at the same height and strictly symmetrical relative to the mirror.
It should be clarified that the place of collection of rays is not quite a point. Since the source of radiation is the projector lens, a beam of light emanating from it is equal in diameter to the entrance aperture of the lens. And in the focus of the rays' return, not a point is formed, but a small circle. To ensure that the shooting lens can accurately reach this place, there is a steering head (Figure IV-8) with two degrees of freedom under the camera mounting platform, and the entire camera with the tripod is mounted on a support that can be moved along short rails (see Figure IV -7).
Figure IV-8. Steering head of the camera tripod.
All these devices are needed to adjust the position of the camera. The maximum brightness of the movie screen is observed in only one place. This brightness of the reflective screen is about 100 times higher than what a diffuse white screen would give under the same lighting conditions. When the camera is displaced by only a few centimeters, the screen brightness drops several times. If the position of the camera lens is found correctly, the camera can make small left-right panoramas around the center axis without affecting the image. Only the axis of rotation should be located not in the middle of the camera (where the thread for the tripod mount screw is made, but in the middle of the lens.so that the center of the lens is opposite the screw in the tripod.
Since the brightness of the reflective screen is 100 times higher, then such a screen also requires 100 times less illumination than is necessary for normal illumination of diffusely reflecting objects located in front of the screen. In other words, having highlighted the game scene in front of the screen with the spotlights to the required level, we must send 100 times less light to the screen than to the acting scene.
The observer, who stands aside from the shooting camera, sees that the scene in front of the screen is brightly lit, but at the same time there is no image on the screen. And only when the observer approaches and stands in the place of the camera, he will see that the brightness of the screen flashes sharply and becomes equal to the brightness of objects in front of him. The amount of light that falls on the actors only from the projector is so insignificant that it is not readable in any way on faces and costumes. In addition, it should be borne in mind that the latitude of the footage is about 5 steps, this is the interval of transmitted brightness 1:32. And when adjusting the exposure for the game scene, the 100x reduction in light goes beyond the range transmitted by the film, the film does not feel such a weak light.
Both the camera and the projector are rigidly fixed on one small platform. The weight of this entire structure is over a ton.
The most important thing, for which it is absolutely necessary to adjust the position of the camera, is as follows. We can see (see Figure IV-7) that actors and other objects in front of the camera cast opaque shadows onto the screen. With the correct alignment of the projector and camera, it turns out as if the light source is inside the shooting camera, and the shadow is hiding exactly behind the object. When the camera is displaced from the optimal position by a few centimeters, a shadow rim appears along the edge of the object (Figure IV-9).
Figure IV-9. Shadows appear on the right behind the fingers due to inaccurate alignment of the camera and projector.
You can see these deviations in the photographs posted in the article “How we shot a performance using front projection” (link will appear soon).
Why do we describe in such detail the technological process of shooting just a few simple plans from the movie "A Space Odyssey"? Because it was this technology for creating combined frames that was used in the Apollo lunar missions.
You understand that it is not for this purpose that they spend a whole year of efforts to shoot a motion picture of how 6 black pigs with proboscis (these are tapirs) graze against the background of the mountain (Fig. III-4). And it is not for this that a gigantic shooting precision construction weighing more than a ton is being erected in the pavilion, in order to eventually shoot a frame in which several boulders and bones lie against the background of an unremarkable mountain landscape (Fig. III-5). On such seemingly passing frames, the technology of shooting general shots on the "Moon" is actually being worked out.
The construction of a combined frame, shot as if on the Moon, begins with the fact that the camera is rigidly exposed relative to the screen, and then the decoration of the space formed between them begins. A front projection screen, like a screen in a movie theater, once hung and fixed, does not move anywhere else. A projection and shooting installation is installed at a distance of 27 meters from the middle of the screen. A slide with a lunar mountain is placed in the projector.
And then, in front of the screen, soil is poured on which actors-astronauts will walk and jump.
The projection camera is located on a trolley and, in principle, can be moved. But it makes no sense to make any movements during filming. After all, if the cart drives up closer to the screen, the distance from the projector to the screen will decrease, and accordingly the size of the lunar mountain in the background will become smaller. And this is unacceptable. The mountain, which is supposedly 4 kilometers away, cannot decrease in size when approaching it by two or three steps. Therefore, the projection camera is always at the same distance from the screen, 26-27 meters. And, more often than not, it is not installed on the ground, but is suspended from the camera crane so that the camera lens is located at a height of about one and a half meters, as if at the level of the camera attached to the photographer's chest. When to create an effectthat supposedly the photographer came closer or took a couple of steps to the side, then it is not the camera that moves, but the scenery. For this, the decoration is installed on a movable platform. The width of this platform is such that it can pass between the camera and the screen and even move under the camera.
According to legend, astronauts on the moon not only did static photo shoots with a Haselblad medium format camera, but also filmed their movements with a 16 mm film camera and recorded their runs on a television camera (Figure IV-10), which was installed on a rover, an electric vehicle.
Figure IV-10. Maurer 16mm film camera (left) and LRV television camera (right), which were allegedly used during their stay on the moon.
Let's try to determine the distance from the reflective screen to the shooting TV camera not from photographs, but from video. We have already provided one of these videos from the Apollo 17 mission. At first, the astronaut stands at the far border of the fill soil, at the screen, literally one and a half to two meters from it (Fig. 47, left). After a few shuffling steps, he begins to skip to run towards the camera. The operator, filming the actor running towards him, begins to zoom out, keeping it at about the same size. Running up to a meter and a half to the camera, the actor stops running in a straight line and turns to the right (Figure IV-11, right).
Figure IV-11. Start and end of the run on the TV camera.
During this run, the actor took 34 steps: 17 steps with his right foot and 17 steps with his left foot. The first 4 steps were not jumping, but simply dragging the feet along the sand (with an iron), in order to stir up the sand, cause splashing of sand from under the feet, moving the foot by 15-20 cm. Further, short jumps begin with a rise of no more than 15 cm (as on Earth), and the main movement occurs due to the movement of the right leg forward 60-70 cm (Fig. IV-12, left) and flight in the air by 20-25 cm, while the left leg is almost not thrown forward (maximum half a step), and stops its move near the right foot. The forward movement of the left leg while jumping does not exceed 30-40 cm (Figure IV-12, right).
Figure IV-12. Moving the right leg (left picture) while jumping and the left leg (right picture).
VIDEO jogging on the TV camera
In total, the movement due to the movement of the right and left legs is about 1.4 meters. There were 17 such paired steps-jumps, from which it follows that the actor ran a distance of about 23 meters. When you double-check the calculations, keep in mind that the first two steps were almost in place.
The actor cannot come close to the screen. Since the screen is mirrored, and the white spacesuit is brightly lit, this screen, like a mirror, will begin to reflect the light coming from the white spacesuit into the camera, and a halo will appear around the astronaut, such as the one we saw in the Apollo 12 mission (Fig. IV-13).
Figure IV-13. Apollo 12 mission. Aura around the white spacesuit due to the mirror screen in the background.
A minimum of two meters should separate the actor from the reflective screen. Two meters from the screen to the starting point of the run, 23 meters - the jump path to the TV camera, and one and a half meters from the TV camera to the finish point. Again, it turns out 26-27 meters. To that mountain against the background that we see in the video, not 4 km from the shooting location, but only 27 meters, and the height of the mountain is not 2-2.5 km, but only 12 meters.
27 meters (90 feet) is the maximum distance that Kubrick was able to move the screen away from the shooting location. For more - there was not enough light.
Kubrick in interviews from time to time complained about the lack of light. When it came to front projection, he said that it was not possible to create the effect of a sunny day on foreground objects. And if we look at the frames of the prologue to "A Space Odyssey", we will indeed see that the decoration in the pavilion (the front of the frame) is always illuminated by the upper diffused light (see, for example, Fig. IV-4, IV-5). For this purpose, one and a half thousand small RFL-2 bulbs, combined into several sections, were hung above the decoration in the pavilion (see Figure III-2). At will, it was possible to turn on or off one or another section in order to more or less highlight this or that part of the decoration. And although the operator tried to create the effect of the setting sun with side spotlights, in general, in all frames of the prologue, where the front projection was used,the foreground always seems to be in the shadow part, and direct rays of the sun do not get there. This information was disseminated on purpose. Specifically, Kubrick said that there is no device as powerful as to create the effect of a sunny day on a 90-foot site. He did it deliberately, because he understood that the film "2001. A Space Odyssey" was a cover operation for a lunar scam, and in no case should all the technological details of the impending lunar falsification be revealed, which would be filmed when imitating sunlight in the frame. A Space Odyssey "is a cover operation for a lunar scam, and in no case should you reveal all the technological details of the impending lunar falsification, which will be filmed when simulating sunlight in the frame. A Space Odyssey”is a cover operation for a lunar scam, and in no case should you reveal all the technological details of the impending lunar falsification, which will be filmed when imitating sunlight in the frame.
In addition, the set to be highlighted was not that big: 33.5 meters (110 feet) - the width of the screen and 27 meters (90 feet) - the distance from the screen. In terms of area, it is about 1/8 of a football field (Figure IV-14).
Figure IV-14. The dimensions of the football field are according to FIFA recommendations, 1/8 of the field is highlighted in color.
And powerful lighting devices existed, but they were not used in the cinema, these are anti-aircraft searchlights (Fig. IV-15).
Figure IV-15. Anti-aircraft searchlights over Gibraltar during a drill on 20 November 1942
For the sake of fairness, it should be added that the most powerful lighting devices used in filmmaking - intense burning arcs (DIGs), come from military developments, for example, KPD-50 - an arc cinema projector with a Fresnel lens diameter of 50 cm (Fig. IV-16).
Figure IV-16. The film "Ivan Vasilievich changes his profession." In the frame - KPD-50. In the frame on the far right, the illuminator twists the coal feed knob behind the illuminator.
During the operation of the lamp, the coal gradually burned out. To supply coal there was a small motor, which, using a worm gear, slowly fed coal forward. Since the charcoal did not always burn evenly, the illuminator occasionally had to twist a special handle on the back of the fixture to bring the coals closer or further away.
There are lighting fixtures with a lens diameter of 90 cm (Figure IV-17).
Figure IV-17. Lighting device KPD-90 (DIG "Metrovik"). Power 16 kW. USSR, 1970s.
Footnotes:
[4] The film "Attack of the Mushroom People" ("Matango"), dir. Isiro Honda, 1963, [5] Taken from 2001: A Space Odyssey - The Dawn of Front Projection https://www.thepropgallery.com/2001-a-space-odyssey …
[6] "American Cinematographer" magazine, June 1968, leonidkonovalov.ru/cinema/bibl/Odissey2001 ….
Chapter V. ZENITH SPOTLIGHTS
In the USA, anti-aircraft searchlights with a mirror diameter of 150 cm (Fig. V-1) were mass-produced for anti-aircraft and marine searchlight installations.
Figure V-1. US anti-aircraft searchlight complete with power generator.
Similar mobile anti-aircraft searchlights with a parabolic mirror diameter of 150 cm were produced in the USSR in 1938-1942. They were installed on a ZIS-12 vehicle (Fig. V-2) and, first of all, were intended for searching, detecting, lighting and tracking enemy aircraft.
Figure V-2. Automobile searchlight station Z-15-4B on a ZIS-12 vehicle.
The luminous flux of the spotlight of the station Z-15-4B could be picked up in the night sky by an aircraft at a distance of up to 9-12 km. The light source was an electric arc lamp with two carbon electrodes, it provided luminous intensity up to 650 million candelas (candles). The length of the positive electrode was about 60 cm, the duration of the burning of the electrodes was 75 minutes, after which it was necessary to replace the burnt coals. The device could be powered from a stationary current source, or from a mobile generator of electricity with a power of 20 kW, and the power consumption of the lamp itself was 4 kW.
Of course, we also have more powerful searchlights, for example, the B-200, with a mirror diameter of 200 cm and a beam range (in clear weather) up to 30 km.
But we will talk about 150-centimeter anti-aircraft searchlights, since they were used in lunar missions. We see these spotlights everywhere. At the beginning of the movie "For all mankind" we see how the spotlights (Fig. V-3, right frame) are turned on to illuminate the rocket standing on the launch pad (Fig. V-4).
Figure V-3. 150 cm spotlight (left) and still (right) from the film "For All Humanity".
Figure V-4. The booster on the launch pad is illuminated by anti-aircraft searchlights.
Taking into account the fact that the rocket is 110 meters high and we can see the beams of light (Figure V-4), it is possible to estimate from what distance the searchlights are shining, this is approximately 150-200 meters.
We see the same floodlights in the pavilion during astronaut training (Figures V-5, V-6).
Figure V-5. Apollo 11 crew training. In the depths - an anti-aircraft searchlight.
Figure V-6. Training in the pavilion. In the back of the hall is an anti-aircraft searchlight.
The main source of radiation in the electric arc is the crater of positive coal.
An intense burning arc differs from a simple arc by the arrangement of electrodes. Inside the positive coal, along the axis, a cylindrical hole is drilled, which is filled with a wick - a compressed mass consisting of a mixture of soot and oxide of rare earth metals (thorium, cerium, lanthanum) (Figure V-7). The negative electrode (carbon) of a high intensity arc is made of solid material without a wick.
Figure V-7. Coal filming white flame for DIG.
As the current in the circuit increases, the arc produces more light. This is mainly due to the increase in the diameter of the crater, the brightness of which remains almost constant. A cloud of glowing gas forms at the mouth of the crater. Thus, in an arc of intense combustion, the radiation of the vapors of rare-earth metals that make up the wick is added to the purely thermal radiation of the crater. The total brightness of such an arc is 5 to 6 times the brightness of an arc with clean coals.
Knowing that the axial luminous intensity of an American spotlight is about 1,200,000,000 candelas, it is possible to calculate from what distance one spotlight will create the illumination necessary for filming at an aperture of 1: 8 or 1: 5.6. Figure III-4 shows a table with Kodak's recommendations for film with a sensitivity of 200 units. For such a film, an illumination of 4000 lux is required at an aperture of 1: 8. For 160 film sensitivity, 1/3 more light is required, approximately 5100 lux. Before plugging these values into Kepler's well-known formula (Figure V-8), there is a very significant correction.
Figure V-8. Kepler's formula linking light intensity and illumination.
In order to somehow simulate the lunar gravity during filming, which is 6 times less than on Earth, it is necessary to force all objects to descend to the surface of the Moon (square root of 6) 2.45 times slower. To do this, when shooting, the speed is increased by 2.5 times in order to get a slow action when projected. Accordingly, instead of 24 frames per second, shooting should be done at 60 fps. And, therefore, the light for such shooting requires 2.5 times more, i.e. 12800 lx.
According to legend, astronauts landed on the moon when, for example, for the Apollo 15 mission (from a photograph of this particular mission - Fig. I-1 - our article begins), the height of the sun rise was 27-30 °. Accordingly, the angle of incidence of the rays, calculated as the angle from the normal, will be about 60 degrees. In this case, the shadow from the astronaut will be 2 times longer than its height (see the same figure I-1).
The cosine of 60 degrees is 0.5. Then the square of the distance (according to Kepler's formula) will be calculated as 1.200.000.000 x 0.5 / 12800 = 46875, and accordingly, the distance will be equal to the square root of this value, i.e. 216 meters. The lighting device can be removed from the shooting location by about 200 meters, and still it will create a sufficient level of illumination.
It should be borne in mind here that the value of the axial luminous intensity given in the reference books is, as a rule, the maximum attainable value. In practice, in most cases, the value of the luminous intensity is slightly lower, and the device has to move a little closer to the object to achieve the required illumination level. Therefore, the distance of 216 meters is only an approximate value.
However, there is a parameter that allows you to calculate the distance to the fixture with great accuracy. NASA engineers took this parameter with special attention. I mean blurring the shadow on a sunny day. The fact is that from a physical point of view, the sun is not a point source of light. We perceive it as a luminous disc with an angular size of 0.5 °. This setting creates a penumbra contour around the main shadow as you move away from the subject (Figure V-9).
Figure V-9. At the base of the tree, the shadow is sharp, but as the distance from the object to the shadow increases, blurring, partial shade is observed.
And in the "lunar" shots, we see blurring of the shadow along the contour (Figure V-10).
Figure: V-10. The astronaut's shadow blurred with distance.
To get a "natural" blur of the shadow - as if on a sunny day - the luminous body of the lighting fixture must be observed at exactly the same angle as the Sun, half a degree.
Since the zenith projector uses a one and a half meter diameter parabolic mirror to produce a narrow beam of light (Figure V-11), it is easy to calculate that this luminous object needs to be removed by 171 meters so that it can be seen with the same angular size as the Sun …
Figure: V-11. Using a parabolic reflector to concentrate radiation.
Thus, we can say with a high degree of confidence that the anti-aircraft searchlight, imitating the light of the Sun, had to be removed by about 170 meters in order to obtain the same blur in the pavilion as on a real sunny day.
In addition, we also understand the motives why astronauts landed on the so-called moon at “dawn,” when the sun rises low above the horizon (Figure V-12).
Figure V-12. The declared height of the sun above the horizon when landing on the moon.
After all, this is an artificial "sun" - it had to be raised to a certain height.
When the searchlight is 170 meters away from the filming location, a mast at least 85 meters high must be built to simulate a 27-30 ° sun rise angle (Figure V-13).
Figure V-13. An anti-aircraft searchlight could be installed on the mast.
From the point of view of filmmaking, the most convenient option is shooting with a low "sun" over the "lunar" horizon, for example, as we see in the photo albums "Apollo 11" and "Apollo 12" (Fig. V-14 and Fig. V- 15).
Figure V-14. A typical photo from the * Apollo 11 * photo album with long shadows.
Figure V-15. A typical shot from the * Apollo 12 * photo album with long shadows.
When the height of the Sun rises above the horizon at 18 ° degrees, the shadow is 3 times longer than the height (height) of the astronaut. And the height to which the lighting fixture needs to be raised will no longer be 85, but only 52 meters.
In addition, having the light source slightly above the horizon has certain advantages - the illuminated area is increased (Figure V-16).
Figure V-16. Change in the area of the light spot at different angles of incidence of the rays.
With such an oblique angle of incidence, the luminous flux from the spotlight is distributed on the surface in the form of a highly elongated horizontal ellipse of great length, which makes it possible to make horizontal panoramas left-right, while maintaining the feeling of a single light source.
In the missions "Apollo 11" and "Apollo 12" the height of the Sun above the horizon at the time of landing is only 18 °. NASA defenders explain this fact by the fact that in the middle of the day the regolith heats up above + 120 ° C, but in the morning, when the sun did not rise high above the lunar horizon, the lunar soil had not yet had time to heat up to a high temperature, and therefore the astronauts felt comfortable.
In our opinion, the argument is not convincing. And that's why. Under terrestrial conditions (depending on latitude), the sun rises to a height of 18 ° in about an hour and a half (more precisely, in 1.2-1.3 hours), if we take the regions closer to the equator. Lunar days are 29.5 times longer than earthly ones. Therefore, the ascent to a height of 18 ° will take about 40 hours, i.e. about two Earth days. In addition, according to legend, the Apollo 11 astronauts stayed on the moon for almost a day (over 21 hours). This raises an interesting question - how much can the soil of the Moon warm up after the rays of the sun have begun to illuminate it, if 2-3 days have passed on the Earth at that time?
It is not difficult to guess, because we have data obtained directly from the moon, from the automatic station Surveyor, when he, in April 1967, measured the temperature during a lunar eclipse. At this time, the shadow of the Earth passes over the Moon.
Figure V-17. Temperature change on the Moon during the passage of the Earth's shadow, according to the Surveyor automatic station (April 24, 1967).
Let's follow the graph, how the temperature of the solar panel changed in the time interval from 13:10 to 14:10 (see the horizontal scale). At 13:10 the station emerged from the shade (END UMBRA), and an hour later, at 14:10, it left the penumbra (END PENUMBRA) - Figure V-18.
Figure V-18. In one hour during an eclipse, the Moon passes the partial shade of the Earth (from the darkness it goes completely into the light).
When the Moon begins to emerge from the shadow of the Earth, the astronaut on the Moon sees how in the deep night the upper tiny piece of the Sun appears from behind the Earth's disk. Everything around begins to gradually brighten. The sun begins to come out from behind the Earth's disk, and the astronaut notices that the apparent diameter of the Earth is 4 times the diameter of the Sun. The Sun slowly rises above the Earth, but only after an hour the Sun's disk appears completely. From this moment the lunar "day" begins. So, during the time that the Moon was in partial shade, the temperature of the solar panel on Surveyor changed from -100 ° C to + 90 ° C (or, see the right vertical scale of the graph, from -150 ° F to + 200 ° F) … In just one hour, the temperature rose by 190 degrees. And this despite the fact that the Sun has not yet come out completely in this hour! And when it peeked out completely from behind the Earth,then already in 20 minutes after this moment the temperature reached its usual value, +120.. + 130 ° С.
True, it should be taken into account that for an astronaut who is at the time of the eclipse in the equatorial region of the Moon, the Earth is directly above his head, and the Sun's rays fall vertically. And at the moment of sunrise, slanting rays appear first. However, the importance of the above graph lies in the fact that it shows how rapidly the temperature on the Moon changes, as soon as the first rays fall on the surface. The sun barely peeped out from behind the disk of the Earth when the temperature on the Moon rose by 190 degrees!
That is why the arguments of NASA's defenders that the lunar regolith has hardly warmed up in three Earth days seem unconvincing to us - in fact, the regolith on the sunny side warms up quite quickly after sunrise, in a few hours, but sub-zero temperatures can persist in the shade.
You all noticed a similar phenomenon at the end of winter - early spring, when the sun begins to warm up: it is warm on the sunny side, but as soon as you enter the shade, it feels cold. Those who skied in the mountains on a sunny winter day noticed similar differences. It's always warm on the sunlit side.
So, in all the "lunar" images we see that the surface is well lit, which means that it is very hot.
We adhere to the version that the effect of the low sun, which is clearly visible in all "moon" images, is associated with the impossibility of raising a powerful lighting device high above the ground in the pavilion.
We have already written that in order to simulate the angle of rise of the sun 27-30 °, a mast with a height of at least 85 meters is required. This is a 30-storey building in height - Figure V-19.
Figure V-19. 30-storey building.
At such a height, you will have to pull powerful electric cables for lighting devices, and change the burning coals every hour. This is technically doable. As well as mounting an external elevator (for a small rise and fall of the lighting device), with the help of which it would be possible to recreate in the pavilion the change in the height of the sun, which occurs on the Moon during 20-30 hours of astronauts stay there. But what is really impossible to do is to build a pavilion so high that the roof is at the level of the 30th floor, and the pavilion itself would be 200 meters wide - after all, you have to somehow carry the lighting fixture to 170 meters. In addition, there should be no columns supporting the roof inside the pavilion, otherwise they will be in the frame. No one has ever built such hangars. And it is hardly possible to build.
But filmmakers wouldn’t be filmmakers if they hadn’t found an elegant solution to such a technically impossible task.
It is not necessary to raise the lighting fixture itself to that height. He can stay on the ground, more precisely, on the floor of the pavilion. And upstairs, to the ceiling of the pavilion, you only need to raise a mirror (Figure V-20).
Figure V-20. Simulate the light of the sun using a light on the ground.
With this design, the height of the pavilion is reduced by 2 times, and, most importantly, when the giant lighting device is on the ground, it is easy to operate.
Moreover, instead of one lighting device, you can put several devices at once. For example, in the 12-episode film "From the Earth to the Moon" (1998, produced and starred by Tom Hanks), 20 lighting fixtures with 10 kW xenon lamps were created in the pavilion. located next to each other directed their light into a parabolic mirror, 2 meters in diameter, located under the ceiling of the pavilion (Figure V-21).
Figure V-21. Creation of the light of the sun “on the moon” in the pavilion using 20 lighting devices and a parabolic mirror under the ceiling.
Stills from the film "From the Earth to the Moon" - fig. V-22.
Figure V-22 (a, b, c, d). Stills from the film * From Earth to the Moon *, 1998
Chapter VI. ZVEZDA TV CHANNEL REPRODUCED THE TECHNOLOGY OF LUNAR IMAGE CAPTURE OF THE APOLLO MISSIONS
In April 2016, just before the Cosmonautics Day, the Zvezda TV channel showed the film Conspiracy Theory. Special project. The Great Space Lies of the United States”, which demonstrated the front-projection technology with which NASA fabricated footage of astronauts on the moon.
Figure VI-1, above, shows a frame taken as if on the moon, with the image of the lunar mountain in the background being a picture from a video projector, and below - the same frame with the projector turned off.
Figure VI-1. Simulation of the astronaut's stay on the moon. Above - the background projector is on, below - the projector is off. Images from the TV show "Big Space Lies of the USA", TV channel "Zvezda".
Here's how the scene looked on a more general plan (Figure VI-2).
Figure V-2. General view of the film set.
At the back of the pavilion, there is a 5-meter-wide scotch-light screen, onto which an image of the lunar mountain will be projected from a video projector. A composition imitating lunar soil (sand, garden soil and cement) is poured in front of the screen - Fig. VI-3.
Figure VI-3. Soil is poured in front of the reflective screen.
A bright lighting device is installed to the side of the screen, simulating, as it were, the light from the sun (Fig. VI-4). Small spotlights allow you to neatly illuminate the area near the screen.
Figure VI-4. The light to the side of the screen will create the effect of light from the sun.
Next, a video projector (on the right) and a movie camera (in the center) are installed. A semitransparent mirror (glass) is mounted between them at an angle of 45 ° (Figure VI-5).
Figure VI-5. Placement of the main elements of the front projection (camera, translucent mirror, video projector, black velvet fabric on the side and a reflective screen in the center).
An image of a lunar mountain from a laptop is transmitted to a video projector. A video projector sends light forward onto a translucent mirror. Some of the light (50%) passes through the glass in a straight line and hits the black fabric (located on the left side of the frame in Figure VI-5). This part of the world is not used in any way and is blocked by black cloth or black velvet. If there is no black absorber, then the wall on the left will be highlighted, and this illuminated wall will be reflected in the translucent mirror just from the side where the filming camera is located, and this is exactly what we do not need. The second half of the light from the video projector, falling on the translucent mirror, is reflected at a right angle and goes to the reflective screen. The screen reflects the rays back, they are collected in a "hot" point. And just at this point the camera is placed. To find this position exactly,the camera is located on the slider and can move left and right. The optimal position will be when the camera is installed symmetrically relative to the semitransparent mirror, i.e. exactly the same distance as the projector.
A person who observes what is happening from the point from which the frame in Fig. VI-5 is taken, sees that there is, as it were, no image on the screen, although the projector is working, and the picture from the laptop is transmitted to the video recorder. The light from the cinema screen is not scattered in different directions, but goes exclusively into the lens of the shooting camera. Therefore, the cameraman who stands behind the camera sees a completely different result. For him, the brightness of the screen is approximately the same as the brightness of the ground in front of the screen (Figure VI-6).
Figure VI-6. This is the picture the cameraman sees.
In order to make the “screen-fill soil” interface less visible, we extended the track left by the rover in the photograph to the pavilion (Fig. VI-7).
Figure VI-7. The track made in the pavilion will connect to the track in the photo. On the right is the shadow of a cameraman with a video camera.
Figure VI-8. Prospective alignment of the track in the pavilion and the track in the photograph. The upper part of the frame is the image from the video projector, the lower part of the frame is the fill soil in the pavilion.
The direction of the light and the length of the shadows from the stones located in the pavilion must correspond to the direction of the shadows from the stones in the picture on the screen (see Figure VI-6 and Figure VI-8).
Looking at Figure V-7, you can see that the video projector is on at this point in time because we see the shadow of a person on the movie screen. The screen is lit with a uniform white background. And although from a physical point of view, the projector illuminates the screen evenly, we see a lack of uniformity in the frame: the left side of the screen is drowning in darkness, and a super-bright spot has formed on the right side of the frame. This is such a feature of a retroreflective screen - the maximum brightness of the screen on reflection is observed only when we stand in line with the incident beam. In other words, we will see the maximum brightness when the light source shines on our back, when the incident beam, the reflected beam and the observer's eye are on the same line (Figure VI-9).
Figure VI-9. The maximum screen brightness is observed in line with the incident ray, where the shadow from the eye falls.
And since we see Fig. VI-7 with the "eyes" of a video camera, through the lens of a shooting camera, the greatest brightness on the screen appears just around the lens. On the right side of the frame, we see the shadow of the cameraman, and the brightest place is around the shadow of the lens. In fact, we observe the indicatrix of the screen reflection: 95% of the light is collected when reflected in a relatively small angle, giving a bright circle, and to the side of this circle, the luminance coefficient drops sharply.
A very important question that arises for everyone who begins to get acquainted with front projection. If a projector casts an image onto a screen, then this projector should also illuminate the figure of the actor who is in front of the screen (Figure VI-10). Why, then, do we not see the image of the lunar mountain on the white spacesuits of astronauts?
Figure VI-10. Light from a projector (pattern stripes) on a human figure. The red circle marks a dark gray filter mounted on the video projector above the lens.
As we mentioned above, a reflective screen does not scatter light in all directions (unlike a white diffuse screen and sand in front of the screen), but collects the reflected light into one small but bright spot. Because of this feature, lighting a movie screen requires 100 times less light than game objects in front of the screen. The luminous flux of an ordinary office video projector was not just enough for an 11 sq. M. Cinema screen. (5m x 2.2m), the luminous flux had to be extinguished with a dark gray glass filter. In Fig. VI-10, we see the illumination of the screen and the bulk soil comparable in brightness, and we see it from the upper angle, and not from the point of installation of the shooting camera. This is not the projector's operating mode, but the detuning mode. But during filming, a dark gray glass filter was lowered in front of the video projector lens, which reduced the luminous flux by about 30 times. This filter (shown in red in Figure V-10) is raised up in frame offset mode.
Without using this filter, an office video projector could illuminate a screen 30 times larger in area, i.e. 330 square meters (33m x 10m) - almost like Kubrick's. We don't have to look for a super-powerful arc projector to light the same screen size that was used at MGM in A Space Odyssey. For these purposes, oddly enough, an ordinary office video projector is quite enough.
"How so? - you ask - why did Kubrick put so much effort? Why did you invent a slide projector of your own design? " And everything is explained very simply. In "A Space Odyssey" the pavilion was illuminated based on a light sensitivity of 160 units, and we used a photosensitivity of 1250-1600 units when shooting. And since we used 10 times the light sensitivity, we needed 10 times less light.
Figure VI-11. Halos along the contour of a brightly lit white spacesuit from behind a glass-mirror screen.
Figure VI-12. To prevent the dispersion of fine dust, the sand is sprayed with water.
As we were informed at the Department of Tracked Vehicles at Bauman University, when the wheels for our future lunar rovers were tested, the sand was wetted with machine oil to prevent the dispersion of fine sand fractions.
Figure VI-13. Wheel lugs at the department of tracked vehicles of the Bauman Moscow Technical Institute.
Figure VI-14. We are conducting an experiment with sand spreading.
Chapter VII. FILM SCREEN GIVEN ITSELF
The Apollo 11 collection contains a photograph taken from the Earth's orbit (Fig. VII-1). In the upper corner of the frame, we see the sun disk with “rays”. The frame was taken with a Hasselblad camera and a lens with a focal length of 80 mm. This lens is considered “normal” (not wide angle) for medium format cameras. The sun occupies a small area of space - everything is as it should be.
Figure VII-1. Sun and Earth Orbital View, NASA image, catalog number AS11-36-5293.
However, in the images of a person's stay on the Moon in 1969-1972, everything is different - a double halo (halo) suddenly appears around the sun and the angular dimensions of the “sun” reach 10 degrees (Fig. VII-2). That's twenty times the actual size of 0.5 degrees! And this despite the fact that the "lunar" images use wider-angle optics (60 mm), and the sun disk should look smaller than on the 80 mm lens.
Figure VII-2. Typical * view of the sun * in Apollo 12 images.
But it is more surprising that in the lunar photographs, an additional galó appears around the giant luminous disk - a luminous ring, a circular rainbow (Fig. VII-3).
Figure VII-3. Apollo 14. Frames with the sun. A luminous ring, a halo, appears around the sun.
We know that under terrestrial conditions, a halo occurs when the sun's rays are scattered in the atmosphere by ice crystals of cirrus clouds (Fig. VII-4), or by the smallest water droplets of fog.
Figure VII-4. Halo around the sun in terrestrial conditions.
But on the moon there is no amosphere, no cirrus clouds, no droplets of fog. Why, then, does a halo form around the light source? Some researchers believed that the appearance of halos in lunar images was indicative of their terrestrial origin (ie, “lunar” images were taken on Earth), and the glowing circle around the light source arises from the scattering of light in the atmosphere.
While agreeing that the "lunar" images are of terrestrial origin, I cannot agree with the thesis that the cause of the halo formation was the scattering of light in the atmosphere. The scattering of light and interference seen in "lunar images" do not occur in the atmosphere, but on the smallest glass balls that make up the scotch light reflective screen (Figure VII-5).
Figure VII-5. Macro photography. The Scotch Light screen consists of tiny balls.
If you take an ordinary LED and place it on the background of the screen made of scotch tape, then a rainbow ring - a halo will immediately appear around the light source, while the halo disappears on the black velvet (Fig. VII-6).
Figure VII-6. The appearance of a halo around the light source due to the Scotch Light located in the background of the screen.
We have prepared a video where we show, being in a bright room, that the halo arises precisely because of the reflective screen. On the background on the left, there is a gray Scotch-light screen, and on the right - for comparison - a gray field of the test scale with the same brightness. And then we replace the gray field with black velvet, turn off the overhead light in the room; First we project the LED onto the black velvet, and then move it onto the Scotch Light screen. Both the halo and the halo around the LED appear only when it is in front of the scotch light.
This is how it looks in the video. HALO APPEARS ON SCOTCH LIGHT SCREEN.
Continued: Part 3
Author: Leonid Konovalov