Camera- An artificial eye
A camera is an optical instrument which uses the light as a medium and captures the images and videos from external field and stores or can transfer to another device. It is a remote sensing instrument from which it can sense external things without any direct contacts. The functioning process of the camera is invented by the human eyes functioning and it just functions in the same way as of the human eyes. Old cameras used photographic films to record the images, and only a limited number of pictures can be taken by that type of cameras. But now there are a lot of storage options available and no limits are there in recording the images or videos. Both the still camera and video camera have the same design and operates in the same functional process, as still cameras record only one static image and video cameras record a series of static images in a continuous way. Several types of cameras are there, such as plate camera, folding camera, Box camera, Rangefinder camera, Instant picture camera, single lens reflex, Twin lens reflex, Large format camera, Medium format camera, Subminiature camera, Movie camera, Camcorders, Professional video cameras, Digital camera, Panoramic camera, Satellite view camera and VR (virtual reality) camera.
A photographic lens is an optical lens in which different assembly of lenses is used for different variants of cameras based on the needed focal length, aperture, and other lighting properties. These lenses are fixed with the body in some variants of the camera and interchangeable in most of the types. Fundamental parameters of the lens are focal length and aperture and these things determine the quality of the captured image. Focal length determines the magnification property of the image and light intensity of the image is controlled by the aperture. Other factors such as focus, shutter speed, white balance, metering, film speed, autofocus point are considered in every image quality. Simple cameras have fixed focus and small apertures to ensure the image within a fixed range. Size of the aperture and external brightness controls the intensity of light entering the lens of the camera during a period of time and shutter controls the length of time that light hits on the image sensors. There are various types and designs in the lenses. One has to choose the lens in a prominent way based on the nature of the work to be undergone. Broadly lens can be overall classified into three categories as a Normal lens, Wide angle lens, and Long focus lens.