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I’m not sure if this is the correct place to put this but I’d assume it’s a photography thing.

In this video When Aldrin is climbing down the ladder of the lander I can see the horizon through him. Why is this?

I’d also like to add that this is not related to moon landing deniers just my own curiosity about how this happens.:)

Thanks guys

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The exterior camera on the LEM was basically a miniaturized television camera, all based on state of the art late 60's video technology.

A television camera looking at the lunar surface in full daylight without even the benefit of an atmosphere to diffuse the harsh light will be extremely susceptible to all the foibles of the video camera tubes of the era.

I will attempt to explain my very layperson's understanding of how this ghostly afterimage of bright objects works, but the details of the electronics involved would be a better subject over on the Electrical Engineering board.

Based on what research I've been able to do, the early Vidicon tubes were particularly desirable for television because, though their signal output was low, their signal to noise ratio was also very high so they could be amplified and could therefore operate indoors very well. The downside being that anything that interfered with the signal at the source would also be amplified and show up on the output image.

One cause of this signal interference is heat buildup from bright lights hitting the imaging surface. This heat increases the electrical conductivity of that area of the imaging surface, essentially amplifying the output in that area slightly and causing an afterimage. Letting this go on for a long time can result in damage to the electrical properties and cause burn in on the image.

The camera spent between 17 and 18 minutes between the time Mr. Armstrong descended the ladder until after the famous descent photo was taken and Mr. Aldrin this video takes place. This is more than enough time staring at the lunar surface to build up enough heat for a strong afterimage. Once something blocked the excess light (like, for example, a giant space suit) the surface is able to cool and the afterimage slowly fades away.

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  • 3
    Beat me to it! The technology of the time used vidicon tubes for imaging. They were very subject to burn-in and lag. Jul 21 at 3:44
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    Yeah, and they put a lot more thought into protecting all the film on the ship. Jul 21 at 3:49
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    Here is an interesting youtube video by Writer/director S G Collins explaining from a photographic perspective why, ironically, we did not have the technology to fake the moon landing in 1969. youtube.com/watch?v=_loUDS4c3Cs Jul 21 at 3:54
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    @user10216038 clearly we just faked it later and then sent it back in time.
    – user253751
    Jul 21 at 10:55
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    I agree with you about everything but the timeline. The Modular equipment stowage assembly containing the camera was deployed by Armstrong after he stepped onto the LEM 'porch'. The first clear TV image was received about 40 seconds later. He reached the bottom of the ladder about a minute and a half after that. Timeline here
    – BobT
    Jul 21 at 15:41
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To get down to the mechanics of how these challenging conditions could enable you to "see through" the astronaut, I think what is happening is this. In a TV camera of that era, the light effectively created an image of electrical charge (or some change in electrical properties) in the imaging surface, and that change was read off by a scanning electron beam. Normally, the electrical changes revert back to zero between each scan, but with such high contrast that was not happening. So a leftover image of the lunar background was slowly fading from the camera tube as Buzz (I said Neil at first but was corrected) stepped down the ladder, creating a double-exposure effect.

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    Bingo. Best answer yet. +1
    – J...
    Jul 21 at 20:26
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    Actually, that's Buzz coming down the ladder. But the rest of the answer is correct.
    – dotancohen
    Jul 22 at 7:44
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    @dotancohen I'm trusting you on that. :-) Jul 22 at 19:29
  • @MarkFoskey If we suppose that history is correct and Armstrong was the first, and further suppose that someone had to hold the camera to make this video, it's a very good guess that the person shown here is Aldrin. There is the interesting case of Armstrong's selfie but nobody agrees with me on that. :-)
    – uhoh
    Jul 24 at 23:55
  • Nobody had to hold the camera for Armstrong. It was mounted on the LM. Jul 25 at 4:09
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The TV cameras of that era were of the vacuum tube type. Artifacts of various types degraded the images they generated. To name a few – ghosting, smearing, burn-in, comet tails, luma trails both negative and postitive and blooming. What you are seeing is a trail of a scan of a bright highlight that is generating a trail. All this was common to TV images of that period.

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