Comments by "Willoughby Krenzteinburg" (@willoughbykrenzteinburg) on "Free Documentary - History"
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To be more specific, star light is actually REALLY dim. The reason you don't see stars in the footage or photographs is the same as the reason you don't see stars if you stand in a bright room until your eyes adjust to that lighting - - and then walk outside. You won't see stars until your eyes adjust to the dark. In other words, your eyes are "set" to expose for a brightly lit room.
The same concept applies to cameras. A camera has several settings which can manipulate how much light hits the film. In this case, the most important factor is shutter speed - or exposure time. In other words, how long is the film actually exposed to the scene letting light in to expose the film? For a brightly lit lunar surface, that's a lot of bright light. The film only needs to be exposed to that light for about 1/60th of a second in order for it to properly expose the film. For pinpoint pricks of starlight? You need at least 10 to 15 FULL SECONDS of exposure time for that light to "burn" the film enough to show up in that photograph. The problem is - there is also a brightly lit lunar surface there - - and if you expose the film to THAT light for 10-15 seconds when anything over about 1/60th of a second is too long, then you would have big problems. The photograph would be so terribly overexposed to light that it would just be a white blob. You STILL wouldn't see the stars because the light from the lunar surface would overwhelm the film and drown out any star light.
For video specifically (it's actually still film, but same concept), it's just a display of still photographs in rapid succession. Something between 24 and 30 "photographs" per second. Also more commonly known as "frames". If you record "video", what you are actually doing is taking a series of photographs. If the camera is taking 30 photographs per second, then clearly, each individual photograph can be exposed to the scene for no longer than 1/30th of a second - because the camera has to move on to the next photo after 1/30th of a second, so it's not possible to expose each frame to the 15-20 full seconds necessary for star light to register on that frame. Ergo, stars don't show up on the "videos".
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