The dawn of the digital format has revolutionised the imaging industry and in turn the way we work our cameras. Furthermore the internal DNA of the camera body has been entirely restructured to make way for the new electrical system; or has it?

In fact film and digital cameras operate in a similar manner. Varying the size of the lens’s diaphragm (aperture) in tandem with the amount of time the shutter is open, focusing light on to the image detection material, the only difference being that this is now received in an electrical rather than chemical form.

A DSLR (digital single-lens refl ex) camera employs a mechanical mirror system that directs the light travelling through the attached lens upwards at a 90 degree angle allowing the photographer to compose the shot through the viewfinder. As the shutter button is pressed the exposure takes place: the mirror swings out of the way and the shutter opens allowing the lens to project the light on to the image sensor. In low light scenarios the shutter will need to stay open for a longer period of time for the image to be recorded, this is why photographers support their cameras with tripods as the smallest degree of camera shake will disturb the quality.

The sensor is formed of millions of pixels laid out in thousands of rows and columns: the more pixels or dots of light, the higher the megapixel count and in theory the higher the resolution. The light travels through a colour filter above the individual sensors and is converted from light waves into an analogue signal which is then processed through a digital convertor. Next the conversion is fine tuned through a series of filters that adjust aspects such as white balance and colour. The resulting image can be made into a JPEG by compressing the file size and discarding unnecessary pixels. The final image is shown on the LCD.
Technology

Inside a DSLR camera

We go under the hood to find out how all the magic happens.
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Pianos work by transmitting the vibrational energy of taught wire strings into a soundboard, which in turn converts the vibrational energy into sound.

The piano achieves this through both its construction materials and action mechanisms. Pianos consist of five main parts: the frame, soundboard, strings, hammers and keys. The frame is constructed from metal and serves as a stable, immobile platform from which its strings (metal wires) and soundboard (vibration to sound conversion mechanism) can vibrate efficiently.

Steel is used as it helps mitigate unwanted vibrational energy being transmitted to the rest of the piano and surrounding area, a problem that leads to distortion of produced sounds. The hammers act as a striking mechanism, and when the piano’s keys are pressed by the player, they rise to strike their corresponding strings in order to produce vibrational energy.

The physics of the piano work in a chain-reaction. When a key on the keyboard is pressed, a complex system of jacks, pivots and levers raise a suspended hammer upwards to strike an overhung string, as well as a string damper (a felt block) that, once the string is stuck, comes into contact with the string and ceases its vibration.

In the short time between the hammer striking the wire and damper ceasing its motion, the vibrational energy is carried down the string and over a ‘bridge’, a raised bridge-shaped structure over which the string is tightly stretched.

The bridge receives this vibrational energy and transfers it into the piano’s soundboard, a wooden board chosen for its resonant properties that through the principle of forced vibration vibrate at exactly the same frequency of the struck string. Consequently, due to the large, expansive size of the board, the quiet tone created by the string is increased, and produces a loud note.
Technology

See inside a grand piano

This annotated cutaway diagram shows what goes on inside the piano when it plays
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