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22 Autumn 2008 ZERB

The Greatest Outside Broadcast Ever

This is the story of how one of the greatest moments in television came about – the transmission, 40 years ago, of live pictures from the Moon. It was truly...

Pictures from the Moon www.gtc.org.uk

by Clive North

22 Autumn 2008 ZERB Pete Conrad with the Apollo 12 Unified S-Band Antenna

With thanks to N

ASA for all images unless specified

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Most people, when they think of the Apollo 11 Moon landings and man’s first steps onto the lunar surface, will recall the names of Neil Armstrong and Buzz Aldrin, and Neil’s famous statement, “One small step for a man, one giant leap for mankind.”

Those steps took place nearly 40 years ago now, on 20 July 1969, and ever since then we have had ingrained on our memories those amazing first moving pictures from another planet – Neil and Buzz’s first steps down the ladder onto the dusty surface of the Moon. But there are two other names which GTC members may not know whose work is almost as closely connected to those events as that of the first astronauts to walk on the Moon – those of Sam Russell and Ed Fendell.

Sam was responsible for overseeing the design and construction of the video cameras that went to the Moon, along with the means of getting their pictures back to the waiting billions of viewers on Earth. Ed was the man whose hands were on the controls in Houston guiding the cameras remotely to send back those unforgettable images.

Sam, now 75, but still working in his own video production company, lives in West Trenton, New Jersey and Ed, now retired, also 75, lives close to his former employer, NASA, at Houston, Texas.

Not long after the launch on 4 October 1957 of the world’s first spaceflight, the Russian Sputnik satellite, Sam found himself on a project with Airborne Instruments Laboratory, Long Island, working in aviation electronics and radar. This soon led to a job with the Flight Control Division of NASA working as a flight controller on John Shepherd’s Gemini III mission - the Americans’ first spacewalk.

Designing cameras for the Moon Sam started designing cameras for taking images from space with RCA (Radio Corporation of America) in 1966. Television was not yet an important part of the Apollo project, hence the use of the so-called Unified S-Bend System, a communications system for transmitting messages to the Moon and for receiving data (biomedical and telemetry) and voice communications. It only allowed a very narrow bandwidth for a television signal.

NASA budgeted only 500kHz for television from the lunar surface, much less than the 4.5MHz standard used for commercial broadcast television at the time. The NASA mission planners called for a lunar camera which could cope with this limitation by using a non-standard slow-scan format of 320 lines resolution at 10 frames per second (instead of the US TV standard of 525 lines at 30 fps).

A team at the Westinghouse Defense and Space Center spent five years developing a camera that was capable of producing a very good black and white picture in the lunar environment with its extreme temperatures and harsh lighting conditions.

On Apollo 11, the first of the missions to actually land on the Moon, this black and white camera was positioned on one of the lunar module’s legs to give a view of the astronauts taking their first steps down the ladder.

Sam recalls, “When I finally saw the television come on and there was Neil Armstrong coming down the ladder – I looked at the image and thought ‘oh gosh, that’s really not a good image’. It was black and white, it was streaky, noisy and hard to see, but thinking about it now I see that perhaps the mistiness or ghostliness of that image added a certain magical quality to it.”

Convoluted routeEveryone saw those historic, indistinct and noisy pictures of Neil Armstrong’s first steps on the Moon but not many realised that the signal quality had been badly degraded en route from Australia to the Unites States rather than on its way from the Moon to Earth. Apollo 11’s historic landing on the Moon came when much of the United States was in darkness and the signal from the lunar module could only be received at two remote tracking stations – at Honeysuckle Creek and a radio observatory at Parkes, both in Australia.

The routing of the signals from the Honeysuckle Creek 85-foot dish station was via the ground lines of the Australian Postal Department to a COMSAT ground station, then to the Intelsat IV satellite over the Pacific back to COMSAT in California, and then via AT&T to Houston where it was converted to NTSC and released to the TV network pool.

This real-time scan-converted TV was recorded on commercial video recorders at the Honeysuckle Creek and Goldstone tracking stations, at the Sydney Video switching centre, as backup, and also at Houston on quad videotape and 16mm film. (Later it was found that a receiver at one particular station could cause picture tearing: a particular model of processing amplifier could convert a slightly noisy received signal into a very objectionable streaky and noisy image. In addition, some of the electronic filters used could cause ringing or ghosting in the image – all potential glitches which were subsequently fixed.)

The worldwide TV audience saw these real-time, scan-converted images but it wasn’t until years later that it was realised how much better the TV pictures would be if the original telemetry tapes could be found and the slow-scan digitally converted to NTSC or PAL. The demodulated slow-scan TV, along with the other data, (voice, space suit parameters, etc) had all been recorded on 14-track analogue data recorders at the tracking stations on 14” diameter reels of 1” wide telemetry tape. Those tapes were an amazing 9200 feet long, ran at 120ips requiring changing every 15 minutes.

This realisation came about late in 2003 when Australian Apollo enthusiast Colin Mackellar saw Polaroid pictures taken of the Honeysuckle Creek tracking station monitors during the transmission and, in 2004, started asking questions about the telemetry tapes containing the slow-scan TV signals.

In mid-2005, some Super 8 footage emerged which underlined the difference in quality of the pictures seen on the Australian monitors compared with the broadcast pictures. The informal search for the tapes was stepped up and by August 2006 NASA had given their support for searching their vast archives. As yet, the tapes have still to emerge - but when they do those images could be sensational…

At the beginning of the American space programme the importance of television had been underestimated but it was not long before there was sustained pressure on NASA to enable the public to watch the flights in real time. There were also continual efforts to upgrade the quality of the television coverage. As a result, Apollo 12 had on board an extraordinary colour video camera.

Sam with Lunar Rover camera replica

Scan-converted image from Apollo 11

Colour wheel

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Early Apollo cameras were designed to produce a good B&W picture for the harsh lunar conditions

BERT SOLTO

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Pictures from the Moon www.gtc.org.uk

Creating a colour image Within that camera, from RCA, was a monochrome sensor coupled to a precision machined gear wheel with six cutouts in which three pairs of red, green, and blue colour filters were mounted. The filters were shaped so that they would evenly expose the sensor during each of the wheel’s 10 revolutions per second, locked to the field scanning rate. Successive TV fields recorded images of red, then green, then blue components. Back on Earth, a scan converter stored the fields on analogue disk drives and from them, generated NTSC video.

All this allowed a simple and reliable camera design. At the time of the Apollo missions, CCDs were hardly more than laboratory curios and the prospect of shrinking a three-tube, broadcast quality camera to shoebox size and keeping it in registration throughout the trans-lunar voyage was unthinkable. The field sequential system offered excellent colour quality and the only risky part was keeping the filter wheel rotating in the vacuum of space.

Ironically, on the GCTA (ground-commanded television assembly) camera’s first trip, Apollo 12, astronaut Alan Bean inadvertedly pointed the camera directly towards the intense light of the Sun and burned out the image sensor. As a result, there was

no television coverage other than the very beginnings of that mission.

Following this, RCA developed the Silicon Intensifier Target tube which had just the characteristics NASA needed for the mission. It was highly sensitive, so could see into deeply shadowed areas, yet it could withstand direct exposure to the Sun without being damaged. It had low lag, or image carryover, from field to field, and its sensitivity was controllable over a 1000:1 range.

Extreme environment for a cameraThere were enormous challenges in producing a good TV picture on the Moon. Although we see the lunar surface as grey, it is in fact very dark grey to almost black in colour. The

astronauts of course have to wear bright, white spacesuits to reflect solar energy. “So you have a scene which is truly black and white, and the need is for the camera to render an image that does justice to both the astronauts and the environment they are working in. We need to see clearly what the astronaut is doing and also what he is working with – that was one of the big challenges,” says Sam.

There were other challenges to overcome too – the camera had mechanical moving parts that had to work, both in a vacuum and in the Moon’s one-sixth gravity. Lunar dust could also get into the camera’s gearing. In addition, there was the problem of temperature control – where the Sun was beating down on the camera the temperature would be around 101°C (214°F) but as soon as the camera went into shade the temperature would plummet to -184°C (-300°F). There was no air circulating around the camera of course to cool it, so a lot of work went into its thermal design.

RCA were following the specifications provided by NASA for the camera but Sam felt that workshop testing was insufficient and that they needed to create a ‘lunar scene’ with a very dark surface with white-suited astronauts to test the camera more realistically – so they set up a model lunar surface complete with toy astronauts.

At this time there was only six months to go before Apollo 15, and RCA was under pressure to get the camera working correctly. The Apollo 14 flight took place halfway through the development of the new camera with its Silicon Intensifier Target tube. There had been difficulties with the ‘14’ camera – a SEC (secondary emission conduction) vidicon Sam recalls - which could expose for the lunar surface correctly but the white

spacesuits of the astronauts appeared ‘bloomy and blurred’. Changes were made to the pickup tube technology but the main approach was to prevent damage to the tube by keeping the camera from being pointed directly at the Sun.

Features from the more advanced studio cameras that RCA were developing were also being incorporated into the new design and NASA changed the cameras’ specification accordingly. “It was like being in a fishbowl,” recalls Sam. “Everyone, NASA management and RCA top management, were watching us!”

Testing, testingSam and his team also had a lot of explaining to do to show that they could get the new camera ready in time for the Apollo 15 flight and their ‘model’ simulations were a successful part of this – so much so that NASA converted a large laboratory into a simulated 20ft x 40ft lunar surface for further tests. Sam remembers mixing sand and soot to approximate the lunar surface – a messy but essential job – and also helping with simulations for the ground controllers who would actually be remotely operating the system. One big key light approximated the light from the Sun.

Environmental testing of the camera was exhaustive and included both

Failed Apollo 12 camera

Apollo 15 Lunar Rover camera

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Lunar Rover with camera and S-Band antenna

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www.gtc.org.uk Pictures from the Moon

thermal and dust tests. One big problem was found and cured – the camera’s spinning filter wheel was found to seize up in cold temperatures. If this happened on the Moon the picture could be obscured by the portion of the filter wheel between the colour filters being stuck in front of the sensor and remaining that way for the rest of the mission.

During final testing there were also many queries about the quality of the picture. “It needed to look as good as the Saturday afternoon ballgame,” recalled Sam “… and if it didn’t meet that criterion, we were in trouble!”

Two factors helped improve the quality of the television picture still further on the later Apollo missions: first, NASA’s Deep Space Network around the world began to make use of new 210-foot dish stations which increased the received signal strength by almost 8dB. Second, Image Transform, then a startup company in North Hollywood, demonstrated to NASA, using Apollo 15 footage, their innovative proprietary system for enhancing video. NASA had them bring their system online for Apollo 16, after which converted video from all the EVAs (extra vehicular activities) was sent to California, enhanced, returned to Houston, and then distributed to the TV network pool - all in real time.

Sam’s particular responsibility as the project engineer was that of pulling all the pieces of the project together

- making sure that the camera met all the requirements, that the astronauts knew how to operate it, the ground controllers knew how it worked and that it mounted properly on both the lunar module and the lunar rover.

Operating the cameraOn the lunar rover, the camera was designed to be operated by the astronauts themselves. It boasted a handle on its base with switches for on–off and exposure mode, and there were levers on the front of the camera for adjusting iris and zoom. The camera was also designed so that it could be put onto a ‘television control unit’ which would receive remote commands from Mission Control who could pan the camera from side to side, tilt it up and down, and also control exposure.

Having ‘dual control’ in this way also caused some unexpected problems in practice. If the camera was mounted on the control unit and the astronaut just wanted to quickly pan the camera, it had to be turnable without wrecking the gearing used for remote control. So a clutch system was added to both the pan and the tilt mechanisms that allowed the camera to be quickly moved by hand.

This seemingly perfect answer actually caused a problem on Apollo 15 when it was found that the tilt clutch got very hot, which reduced its effectiveness so much that when the camera was tilted up a little it would flop backwards and end up pointing straight up.

The tilt clutch could have proved a big problem at the end of that mission when it was planned that the camera would televise the lift-off as the lunar module lifted the astronauts back up to lunar orbit. Mission Control decreed that the camera should be locked off

horizontally rather than risk a tilt up, just in case the camera flipped up and become uncontrollable. Once the astronauts had left, the camera was needed for further science experiments including the camera panning slowly round and mapping the area.

One problem that did turn out worse than expected on Apollo 15 was lunar dust. Precautions against ingress of dust into the camera and its Angenieux 15–75mm lens had worked fine – the problem was the dust that was kicked up as the lunar rover

drove around. This settled on the lens causing distracting speckles whenever the camera pointed anywhere near the Sun. The astronauts had to clean the lens frequently with a brush. There was also no sunshade on the camera – an omission that would be corrected on all subsequent flights.

Multiple camera positionsOn the Apollo 15 flight the camera was used in three very different ways. After landing, the astronauts pulled a lanyard which released a trapdoor on the side of the lunar module exposing the camera. This was pointed towards

the ladder to show the astronauts climbing down onto the lunar surface.

Sam recalls: “We saw Dave Scott climbing down … the picture was in sharp focus and the rendering was perfect … we saw the astronaut in complete detail ... that really was a moment of joy – we knew we had it made and the worries were pretty much over!”

The second camera position was to cover the deployment of the lunar rover which was to be unloaded from

the opposite side of the lunar module. The camera had to be set up on a tripod on the lunar surface and linked by cable back to the spacecraft. An umbrella-shaped high-gain antenna was fixed to the lunar rover for direct transmission of pictures back to Earth, via a communications unit which handled both the TV signals and the astronauts’ communications.

The ability to remotely-control the camera was invaluable – it meant that the astronauts could move away, carry out their experiments and explore while the camera followed their

Angenieux lens after dust test

Apollo 16 Commander John Young enjoys one-sixth gravity

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Pictures from the Moon www.gtc.org.uk

every move. TV pictures couldn’t be transmitted while the lunar rover was travelling though – the directional antenna was not designed to automatically orientate itself towards Earth so this had to be done manually each time the vehicle stopped.

Ironically, given the fact that this was the first time astronauts were to venture far away from their spacecraft and that there would be live colour TV coverage for the first time, the three American TV networks had only planned sporadic coverage. When they saw the feed of the Apollo 15 pictures though, with their detailed views of the explorations, they dropped their regular programming and devoted their airtime to the live coverage.

Go several seconds before ‘Action’!Controlling the camera on the Moon from back on Earth proved more than a little tricky - quite simply because it was so far away and the various stages in the radio signal’s path added a delay of around six and a half seconds. Also, the camera remote controls were quite crude. The flight controller had just a set of buttons with which he could command the camera to pan left or right, tilt up or down, or zoom in or out. Each move also had to be followed by a ‘stop’ command. “They were just punch-button commands and they were really not very elegant!” recalls Sam.

The result was that the flight controller in Houston had to be

constantly thinking and planning ahead as each camera move had the time delay to compensate for. He would have to give his commands well in advance – luckily the fixed speed pan was quite slow.

Chief Camera Controller was Ed Fendell who found that, as well as the radio delay, it was very difficult to predict what an astronaut might do next – whether he would move left or right for instance. The chances were, however, that he would either move out of frame, or if Ed took a guess and panned, it would be in the wrong direction. The solution was to zoom out at the first sign of an astronaut making a definite move and then tighten in again when the move finished. Fairly standard stuff on Earth but not so easy when separated by 240,000 miles and a six and a half second command delay!

Ed remembers: “This way of operating was so intense and tiring. It was very different doing it for real rather than simulating it at Cape Canaveral. It wasn’t helped by the adrenaline pumping and the thought that there

were 9 billion people looking over your shoulder!”

At the first lunar worksite he was no doubt relieved to see the remote control system operate successfully delivering a wide-angle pan of the lunar surface. “I remember thinking this really is the Moon! It’s not like looking at some simulation at Cape Canaveral - this is for real! … When I started to look at the astronauts later on and at the colours of the emblems on their suits and the fact that they were moving I can only guess what my blood pressure went to! It was extremely exciting but there really wasn’t time to do anything but keep on working.”

“When the crew came to a stop on the lunar rover, they adjusted the antenna to point to Earth and said the camera’s ‘all yours’. It was, er… a little tricky and kind of sweaty!” jokes Ed.

As well as receiving requests for camera moves from the scientists and engineers in Mission Control, Ed also had communications direct from the astronauts asking what he was looking at with the camera and how it was all going. At each stop on the lunar rover trips there was a requirement for a 360° pan of the area for the geology team. This was taken in 3° increments, then the camera had to find and observe the astronauts again.

“You have to understand we were not television, or camera, people. We were assigned to this job and we went off to do it, but as soon as the press got word of what we were doing the media descended on us for interviews and the next thing I knew was my name was known around the world - and I was just a flight controller at NASA!” said Ed.

Apollo 15 had been the first time the camera had gone mobile with the lunar rover. A lot of pre-planning had been done with both the Earthbound geologists and the astronauts on the best way to televise the various planned stops on Dave Scott and Jim Irwin’s lunar surface excursions. NASA’s public relations people and the

flight director also had requests for particular coverage from the camera and these had been rehearsed as well as they could be on Earth. In the end the coverage was so gripping that all the American channels showed the live coverage from start to finish.

Capturing the lift-offExtraordinary though it may seem now, when Apollo 16 came around the gloss seemed to have worn off as far as the American viewing public was concerned. The networks only showed portions of the coverage but in Europe, at least, the non-commercial channels cleared the schedules for it.

All this came to a head when it was planned to show the blast-off of the ascent stage of the lunar module from the Moon’s surface. On Apollo 15 there had been the problem with the clutch on the pan and tilt head meaning the camera had remained static with the spacecraft rapidly exiting the top of frame. For Apollo 16, the tilt clutch problem had been solved and Ed Fendell asked RCA to establish how the ascent stage should be followed and at what point the remote command should be given for the camera to tilt upwards following the ascending spacecraft.

Sam had done the calculations but there was another, unforeseen, problem. The astronauts had placed the lunar rover, with the camera, much too close to the lunar module so when the ascent took place the spacecraft still shot straight up out of frame and there was still no chance of following it.

Apollo 15 ascent - slow-scan still frame

Ed Fendell with gold camera award

Buzz Aldrin - pictured by Neil Armstrong

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By the time of Apollo 17 – the final mission – the flight controllers had got it just right. By looking at the size of the image of the lunar rover on the TV screen they were able to work out just how far away the lunar module was from the now remotely positioned camera.

“What I was watching to get those pictures was a sheet of paper,” said Ed. “The camera commands started going out pre lift-off as the crew was counting down. We had to get the camera moving well before the lunar module lifted off”.

After the calculations had been done and applied, the camera zoomed back and tilted up exactly as the lunar module took off. In fact, Ed had commanded the camera to move a full eight seconds before the ‘Fire’ button was pushed in the lunar module. The camera carried on tilting up and zooming after the retreating ascent stage, following it as it went up and pitched over, establishing the velocity that it needed to go into lunar orbit. The spectacular shot carried on and on until the spacecraft was just a speck

of light fading from the screen.After his unique spells of camera operating, Ed took a trip to Germany to receive a golden miniature model camera which was presented to him, by a German TV magazine, as a memento of his work with the Apollo project.

Sam comments: “I think it’s hard to understand the challenges we had in doing the camerawork on Apollo. You have to remember the time was 1970. At the time integrated circuits hardly existed and there were next to none on the cameras. We used a very crude colour system, a colour wheel in front of basically a black and white camera but it was a system that worked - and that was the important thing.”

It was a personal disappointment for both Sam and Ed that the space programme ended early after Apollo 17 – as it no doubt was for many of the other 400,000 people who had been employed around the US on the Apollo project. Originally planned to go on to Apollo 20, it was felt that the public had had enough of space flight – to the Moon anyway – and the

remaining Saturn V rockets, lunar modules and lunar rovers went to museums and into storage.

Sam summed it all up: “After Apollo 17 it was never the same again – there was something missing, that sense of exploration, of pushing the frontier, the feeling of really being in the blue sky arena - it was all gone. We stepped back and we did the space station and all of those things, but I think that the goal of getting to the Moon, exploring and bringing the men back was just an extraordinary venture. I’ll never forget it.”

But it was still the greatest OB ever!

My thanks to Sam and Ed for their cooperation in the preparation of this article, which came about as a result of interviews I filmed with them for a Discovery Science HD series Moon Machines, produced by Dox Productions (Clive North).

www.gtc.org.uk Pictures from the Moon

Moon Machines interview with Sam Russell

Fact FileClive North is a UK-based freelance lighting cameraman. His documentary feature for Dox Productions ‘In the Shadow of the Moon’ was recently shown on Channel 4 following its cinema release in the US, UK, NZ and Australia.

Website: www.clivenorth.co.ukMobile: 07831 879594Sam Russell: www.russelland.com

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