Digital Photography Technology

The history of photography started sometime after 322 BC when the first laws of optics were discovered and the phrase camera obscura was first used.

If you were to stand in completely dark room on a sunny day, make a very small hole in a window covering, there you would see the outside projected on the opposite wall, only up side down. This has been know as a basic physics law and understood by Aristotle (384-322BC). <p> The words “camera obscura” are Latin for dark room.

This phenomena is explained by the first law of optics. Light travels in a straight line and when some of the rays reflected from a bright subject pass through a very small hole in thin material, they do not scatter but cross and reform as an upside down image on a flat surface held parallel to the hole. This law of optics was known in ancient times.

The Islamic scientist and scholar, Alhazen (Abu Ali al-Hasan Ibn al-Haitham) (c.965 – 1039) gave a full account of the principle

of this physics law of optics.

In 1490 Leonardo Da Vinci gave two clear descriptions of the camera obscura in notes that he had written. Many of the early ones were large rooms.

Eventually, in the late 16th century, a convex lens replaced the small hole which improved the image quality. Mirrors were used to position the image where it was more easily observed.

The image quality was improved with the addition of a convex lens into the aperture in the 16th century and the later addition of a mirror to reflect the image down onto a viewing surface. Giovanni Battista Della Porta in his 1558 book Magiae Naturalis recommended the use of this device as an aid for drawing for artists.

Johannes Kepler, a German astronomer, was the first to use the term “camera obscura” for making drawings of the stars. Artists, in the 17th and 18 century used the camera obscura to help them in their work.  This was a optical device that would display a persons features on a canvas or paper to help an artist make an accurate drawing or painting.

By the 19th century is was getting close to the time when someone would marry the camera obscura and light sensitive material to make the camera as we know it today.