You can assemble your own camera from a cardboard box and use it to look at the world with completely different eyes. Through the laws of physics, inside the box, the image in front of the camera suddenly becomes the bottom and the left becomes the right. Just as the inventors of the camera saw it a long time ago.
The cardboard box can be the size of a shoebox, but it can also be larger or smaller. The main thing is to keep it tight, so that it doesn’t let any light in from outside.
You will also need parchment paper, baking paper or very thin printing paper. You will also need non-transparent adhesive strips. Moreover, you need a pair of scissors, a needle or a paper clip as well as a blanket, a large towel or a larger piece of clothing.
Cut a hole out of the cardboard box, this will later become your “screen”. Look inside the box and tape up the places where light still shines in. Now cut out a small hole on the opposite side of the screen (3 cm x 3 cm is enough). Tape the hole shut so that no more light shines through. Then poke a tiny hole in the tape with a needle or paper clip.
Now it’s time for the screen. Stick the parchment or baking paper over it. The camera obscura is ready. Now hang a blanket over your head and you will see your surroundings upside down and inverted on the screen. If it is brighter outside, the picture will be easier to see. If you paint the inside of the box black, the image on the screen will be even brighter, but more blurred.
You can find detailed instructions here.