Camera Obscura

A camera obscura is a box of varying size with a single hole in one of its walls. Light from an external scene enters through the hole and projects an image onto the opposite inner wall. Parallel beams of light reflected from the subject (e.g., a wagon) pass through the hole, creating an image on a screen or paper inside the box. A smaller hole results in a sharper image but reduces brightness. Since this setup creates a real central projection, the images produced have an accurate perspective. A pinhole camera, a type of camera obscura, has an absolute depth of field, meaning it can capture both near and distant objects with high sharpness in a single image. **Pinhole camera** The image formed by a pinhole camera is real, as the light rays from the object (such as a wagon) physically land on the matte paper. However, the image is inverted, appearing upside down on the screen inside the box. **Construction with a mirror** By incorporating a mirror, the inverted image can be flipped to appear in the correct orientation. **Construction with a lens** Adding a lens to the design permits a larger opening without loss of image sharpness.