The Lack of Stars in the Pictures of Space

In many pictures taken from space, stars are not visible, even with a dark sky. The reason is that stars are very dim compared to the primary object in the pictures. If the camera is set to take a correctly exposed image of an object that is much brighter than the stars, then the stars would not be visible in the picture. The same thing would happen everywhere, in space, or on the surface of the Earth.

Flat-Earthers often take the lack of stars as fakery. They are wrong. This is simply a limitation of any camera.

In the illustration, the left picture was taken when the surface of the Earth is in the day, and the right picture was taken during the night.

In photography, the sunny 16 rule is a method to estimate the correct exposure in the daylight, which is ISO 100, f/16, 1/100s. The left picture was taken using ISO 200, f/10, 1/640s; or only a third of a stop difference from the sunny 16 rule. If taken using this exposure, stars would not be visible in the resulting picture, the same way we generally can’t see the stars during the day.

The right picture was taken using ISO 12800, f/1.4, 1.3s. Or 21⅓ stop more exposure than the left picture. This allows the camera to capture about 2640000× more light and makes the stars visible in the resulting picture. In the picture, the surface of the Earth is dark, and its intensity does not differ much from the stars.  Both the surface of the Earth and the stars can be captured in a single frame with the correct exposure.

If the left picture is taken using the exposure of the right picture, the Earth would appear as bright white and no longer resemble the Earth we know. On the other hand, if the right picture is taken using the exposure of the left picture, the camera wouldn’t be able to gather enough light, and everything will appear pitch dark.

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