YOU HAVE TO STAND ON YOUR HEAD TO PROPERLY VIEW A PINHOLE IMAGE
Now here's a fact that has fascinated humans for centuries. A pinhole aperture, as the sole source of light entering a dark chamber, will project an upside-down, laterally reversed image of the exterior scene onto a surface inside the box. This is true regardless of the size or shape of the box.
Consider the example of a walk-in pinhole camera - an actual room, say 10 feet by 10 feet and 8 feet high, with every source of light blacked out except for a hole in one wall of about a half-inch in diameter. If you are inside, you will see (once your eyes adjust to the low light level) an image of the outside world, upside down and reversed side to side on the opposite wall.
If you attach your camera (digital or film) to a tripod, focus it on the image on the wall and set your shutter for a long time exposure, you can make an exposure of the scene that is being projected on the wall. You will have to experiment with exposure times since every scene will have its own brightness level. It may take as little as 15 seconds or as long as several minutes. Curiously, if someone walks through the outside scene, you can see their image walking across your interior wall - like a movie projector. Because the person is moving, he or she will likely not be captured by your camera, except perhaps as a blur.
A very small box, say a matchbox, with a pinhole of one tenth of a millimeter, will also contain a similar image. Of course you can't be in the matchbox to see the image, but you can record it by using film or photo paper.
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This image is upside-down - exactly as seen by the camera obscura or the pinhole camera. At first, it may not look upside-down because most of it is a reflection, but look closely, and you will see the shoes which are not a reflection.
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