The most important tool of photography is the camera itself. Basically, a camera is a lighttight box with a lens on one side and light-sensitive film on the other.
Parts:
1.camera box
2.film
3.aperture or diaphragm and shutter
4.the lense
5.the viewing system
Cameras may work with the light of the visible spectrum or with other portions of the electromagnetic spectrum. A camera generally consists of an enclosed hollow with an opening (aperture) at one end for light to enter, and a recording or viewing surface for capturing the light at the other end. A majority of cameras have a lens positioned in front of the camera's opening to gather the incoming light and focus all or part of the image on the recording surface. The diameter of the aperture is often controlled by a diaphragm mechanism, but some cameras have a fixed-size aperture.
Refraction is the phenomenon which makes image formation possible by the eye as well as by cameras and other systems of lenses. Human eyes have often been compared to cameras. They are alike in terms of structure, but they have one fundamental difference in functioning mechanism.
Similarities & the Difference between Camera and Human Eye
Similarities:
1. opening for light to enter aperture in Camera and pupil in eye.
2. control the amount of light entering camera/eye.
diaphragm control size of aperture in camera and iris muscles control size of pupil in eye.
3. refract light glass biconvex lens in Camera .And mainly cornea ; lens, aqueous & vitreous humor in eye.
4. object of light action to form image photosensitive chemicals on film in camera and photoreceptors(rods & cones) in retina of eye.
5. absorb excessive light to prevent multiple images formation dark internal surface in camera and pigmented, dark choroid in eye.
Difference:
1. focusing mechanism change distance between lens & film in camera and change focal length of lens using ciliary muscles in eye.