Tag: f-number

Camera Exposure Settings in the Apollo Missions

Cameras used by Apollo astronauts were equipped with ASA 160 film (equivalent ISO 160 in digital cameras). And they were instructed to use the following camera exposure values: shutter speed 1/250s, aperture f/5.6 (in shadow), and f/11 (sunlit). We can try the same values to everyday scenes and see how they end up in the results.

Stars are not visible in the photos from the Apollo missions, and flat-Earthers use the fact to dismiss them as fake. In reality, by using the same exposure settings as the astronauts used, we cannot get the stars to appear either. Therefore, there is no reason to expect stars to appear in photographs taken by Apollo astronauts.

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Camera Entrance Pupil Size and the Zoom Factor

The entrance pupil is the opening in front of a camera that allows light to enter. If it is partially obscured, light can still come through the unobscured part, and the camera can still see the object.

In one of those “experiments,” flat-Earthers placed an obstacle in front of a camera, very close to the lens, so that an object is partially visible. At the widest angle setting, the person appears partially visible. But it turned out that zooming in will fully reveal the person. Flat-Earthers claim it is how objects can vanish behind the horizon if Earth is flat and how they can reappear by zooming in. In reality, zooming enlarges the camera’s entrance pupil, letting the camera to see over the obstacle.

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