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Using the incredible site: https://apolloinrealtime.org/11/ as it replays the entire mission in real-time.

One great feature is that the site plays the in-flight TV transmissions that the crew made from the Command Module / LM spacecraft as they journeyed to the moon.

The quality of the pre-landing / in-flight TV is amazing - so much so that Charlie Duke (Capcom) at 0:56:00+ hours into the flight noted to the crew:

"11, Houston. we can make out the markings on the [LM] panel...the, it's really unbelievable, the definition we're getting down here off that little camera...we can even see the barber pole on the talkbacks...we can read the markings for the [various readings]. You can even read the scale on the eight ball"

enter image description here

Yet - we are all familiar with the grainy and ghostly transmissions of the first step from the surface of the moon on the same flight:

enter image description here

If the technology was such that Mission Controllers in Houston could literally read the markings on the instrument panels during one TV broadcast, why was that same level of detail not available on the surface of the moon?

I'm not sure if this question answers mine and I'm just not clever enough to realize it :)

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  • $\begingroup$ I think you are comparing a color film shot to a live slowscan black and white video transmission. The film developed on Earth after landing. The film with 30 fps (frames per second), the slow scan tv with only 10 fps. $\endgroup$ – Uwe Jul 18 at 22:46
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    $\begingroup$ "The portion of the broadcast spectrum traditionally used for video was sending vital ship data to Earth....320 scan lines at 10 fps, transmitted at a meager 500 kHz". This answers your question: they don't have enough bandwidth(too far). 500K is really tight: with 16000(two fields interleaved to one frame) scan lines per second it's like 30 cycles per line, equivalent to maybe 60 pixels per line? $\endgroup$ – user3528438 Jul 18 at 22:51
  • $\begingroup$ If you remember the movie The Martian. when the ship approaches earth, it gets more and more bandwidth, from email to broken videos calls to HD video calls. Distance matters. $\endgroup$ – user3528438 Jul 18 at 22:54
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    $\begingroup$ @Uwe No, the color shot here is live, not film. $\endgroup$ – Russell Borogove Jul 18 at 23:22
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Summary: It took development time to adapt the color TV camera used inside the command module to the extreme temperature, vibration, and vacuum of the lunar surface. By Apollo 11, only the "indoor" color camera was ready.

Three models of television cameras were used in the Apollo program.

  1. The Command Module TV Camera System was a black-and-white TV camera used only in the CM only on Apollo 7-8. Those missions had no LM and no EVAs.

  2. The Lunar-Surface TV Camera System was a black-and-white TV camera rated for the extremes of the lunar surface. It was used only with the LM on Apollo 9 and 11. Often called the "slow-scan" camera, they had poor resolution, scan rates, and picture quality.

    This is the source of the low-quality pictures seen on the lunar surface during Apollo 11.

These previous two low-quality models were used early in the program because the communication bandwidth was not available:

As the Apollo Program progressed, higher gain antennas became available and more weight was allotted to the television equipment. These developments made possible the use of a television camera with standard commercial scanning rates, thereby eliminating the picture-smearing effect associated with the slow-scan motion rendition.

  1. The Color TV Camera System was a color TV camera. It was developed quite late in the Apollo program:

    In late 1968, several systems for transmitting color video information from an Apollo spacecraft were investigated and evaluated by MSC personnel whose objective was to provide a color TV camera for the Apollo 10 mission.

    Compared to the previous TV cameras, not only was it in color, but it had a higher resolution, scan rate, and picture quality. They were used inside both the CM and LM for Apollo 10. Because that mission did not land all the way on the moon, those cameras did not need to be rated for the extremes of the lunar surface. It was a success, and was used inside the CM for all remaining Apollo missions. This is the source of the high-quality pictures you saw in the Apollo 11 CM.

    However, this camera was quite fragile. It used a spinning color wheel to separate the RGB components, and was not rated for the temperatures, vacuum, and dynamic light levels that occurred on the moon. By Apollo 12, a version suitable to use on the moon was created:

    In the weeks before the Apollo 12 mission, a decision was made to attempt to build a TV camera that would generate a field-sequential color video signal and thereby provide color telecasts from the lunar surface. The camera chosen was the same type used in the Apollo 10 CM, but modified to withstand the rigors and vibrations in the LM during the launch and the extremes of the lunar thermal/vacuum environment.

But that lunar color camera simply wasn't available for Apollo 11.

Source: Apollo Experience Report: Television System NASA Tech Note D-7476

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    $\begingroup$ Contributing to the bad quality of the Apollo 11 moon camera was that the actual signal was not compatible with the US broadcasting standard NTSC and first had to be converted. This was done by projecting the received signal on a monitor which was then filmed by a conventional TV camera. The raw signal was also recorded. People recorded the already bad TV version and this is what you often get to see in videos today, not the actual raw version whose quality is better. $\endgroup$ – DarkDust Jul 19 at 6:25
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    $\begingroup$ Unfortunately, for Apollo 11 the raw recordings were lost. $\endgroup$ – Hobbes Jul 19 at 6:36

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