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Science and Technology: research lens in a camera. Understanding camera lenses can help add more creative control to digital photography. Choosing the right lens for the task can become often complex but is of the most utter importance to project the most perfect perspective one can get. Lenses are pieces of glass that bend light and form images. The lens bends light as it goes in and again as it comes out, each section of a lens acts like a tiny prism. When refraction is at work in a prism it breaks the beam of visible light into its basic colours. In visible light, the magic colours you can see are red, orange, yellow, green, blue, indigo, and violet. Scientists say ROY-G-BIV. What makes lenses expensive is the special coating they hold to reduce the colour spreading of the prisms. There are two main types of lens :
Convex lenses are thicker at the middle.
Rays of light that pass through the lens are brought closer together (they converge). A convex lens is a converging lens. When parallel rays of light pass through a convex lens the refracted rays converge at one point called the principal focus. The distance between the principal focus and the centre of the lens is called the focal length. Real images are created by the convex lens. A camera consists of three main parts:
The body which is light tight and contains all the mechanical parts.
The lens which is a convex (converging) lens).
The film or a charged couple device in the case of a digital camera.