The Photography is the procedure and art which enables set and reproduce , through chemical reactions and on surfaces prepared for it, the images They are collected at the bottom of a dark chamber.
The principle of dark camera It consists of projecting the image that is captured by a small hole on the surface. In this way, the image size is reduced and can increase its sharpness.
The storage of the image obtained can be done in a sensitive film or in CCD and CMOS sensors or digital memories (in the case of the so-called digital photography ).
He daguerreotype , invented by Louis Daguerre in 1839 , is considered as the precursor of modern photography. Daguerre He used a layer of silver nitrate on a copper base. The positive was reflected in mercury and the image was fixed by introducing the plate into a solution of sodium chloride or dilute sodium thiosulfate.
George Eastman He was a great driver of photography when, in 1888 , introduced the first camera Kodak With roll of photo paper. This technique replaced glass plates. Another important step occurred in 1948 , with the launch of the technique Polaroid which allows to reveal the photos in just one minute.
Currently, photographs are often retouched with software to eliminate those imperfections that have been registered and perform all kinds of actions, such as highlighting colors, playing with the focus or superimposing various images on the same, for example.
It is important to keep in mind that, in addition to being used for scientific purposes, photography has become a art . The images taken by artistic photographers are usually displayed in exhibitions and museums.
The most important parts of an SLR camera are: the objective (formed by the lenses that are responsible for directing the light towards the sensor to achieve the best fidelity to the scene that you want to capture. According to the diaphragm, the objective can be more or less bright), the shutter (It is formed by a set of blades that allow the passage of light, controlling the amount that must enter; the viewfinder(allows the photographer to see the scene and choose the reason for the image) and the sensor (It is responsible for capturing the information of the scene; it is formed by pixels that are sensitive to the light that record the image data that will be subsequently processed).
Photography as a record of life
Throughout history, human beings have known how to use different tools that he had at his disposal to leave records of his passage through this world and of those events that would mark a before and after in the history of mankind.
And the discovery of photography and the advances that were taking place over the years in it, allowed us to later have a notion of certain things that happened a long time ago and that greatly affected societies around the world, like World War II. It was thanks to photography and literature that there was a true notion of the atrocities committed by the human being against the species itself under artificial arguments and supremacist speeches.
With the advancement of technologies, photography has become available to everyone, allowing each person to have a mobile device You can capture images and keep them forever, sharing them with your friends. Also, the rise of social networks as Facebook allows the tools to share images to be more instantaneous and public, getting an image to travel all corners of the globe in just seconds.