Where Have All The Stars Gone ?

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Offline neilep

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Where Have All The Stars Gone ?
« on: 02/04/2009 02:38:58 »
I know I have seen the explanation to this before (ususally in the conspiracy theory threads) but can someone explain again why I can't see any stars in this picture ?


Or is the whole Space Shuttle/Space Station thing a hoax ?

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Offline Karen W.

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Where Have All The Stars Gone ?
« Reply #1 on: 02/04/2009 02:47:38 »
I never noticed that in pictures before!

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Ethos

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Where Have All The Stars Gone ?
« Reply #2 on: 02/04/2009 02:50:06 »
I believe the answer to this is; The time exposure needed to make the stars visable is not necessary when taking these pictures of the space station.
« Last Edit: 02/04/2009 02:55:09 by Ethos »

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lyner

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Where Have All The Stars Gone ?
« Reply #3 on: 02/04/2009 10:34:46 »
It may be easier to discuss if you imagine that the photo were taken with a simple digital camera. If the sensor used 8 bits, that would give 256 possible brightness levels. If you exposed the picture so that the brightest highlight was level 256 and the brightest star in the picture had a brightness of less than 1, it would not be displayed.
The range is actually much more than 1:256 in the scene in the picture so, even though film has a wider contrast range, the effect of flare (light being spread all over the picture from the brightest areas) means the stars will never show.
Let's face it. To take a picture of the stars from Earth, at night, you'd need a wide lens / long exposure which would be totally unsuitable for sunny holiday snaps.
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