A History of Field View Cameras
When you think of photography, you may think of it as a fairly modern invention. On the contrary, photography began with the camera obscura as early as the 10th century AD, and some evidence seems to indicate that Aristotle was familiar with this technique as early as the 4th century BC. The camera obscura was a darkened room with a tiny hole in one wall with a white screen on the opposite wall. In the middle of the 16th century, lenses were added to the hole of the camera obscura to produce a brighter, sharper image. Over time, the camera obscura became more compact, and the image was projected onto thin paper on glass so it could be traced. This was used as a sketching aid by artists.
Sketching the images on the camera obscura took extra time, but in 1725 Johann Heinrich Schultz learned that exposing certain silver salts to light could capture the image without tracing. Over the next 75 years, scientists investigated these properties of the silver salts, but none could practically use the discovery to produce permanent images.