Seismology

Seismology (/saɪzˈmɒlədʒi/; from Greek σεισμός "earthquake" and -λογία "study of") is the scientific study of earthquakes and the propagation of elastic waves through the Earth or through other planet-like bodies. The field also includes studies of earthquake environmental effects, such as tsunamis as well as diverse seismic sources such as volcanic, tectonic, oceanic, atmospheric, and artificial processes (such as explosions). A related field that uses geology to infer information regarding past earthquakes is paleoseismology. A recording of earth motion as a function of time is called a seismogram. A seismologist is a scientist who does research in seismology.

History

Scholarly interest in earthquakes can be traced back to antiquity. Early speculations on the natural causes of earthquakes were included in the writings of Thales of Miletus (c. 585 BCE), Anaximenes of Miletus (c. 550 BCE), Aristotle (c. 340 BCE) and Zhang Heng (132 CE).

In 132 CE, Zhang Heng of China's Han dynasty designed the first known seismoscope.

Seismic (album)

Seismic is the seventh studio album by San Diegan punk band Dogwood, originally titled Your Tongue Is the Deadliest of Arrows by the band. Artwork photos feature former members Scott Bergen and Eddie Spangler, although they did not perform on the album's recording, and both had left the band by the time of its release. Bassist Jason Harper announced he was leaving the group during the album's recording.

Track listing

Photography

Photography is the science, art and practice of creating durable images by recording light or other electromagnetic radiation, either electronically by means of an image sensor, or chemically by means of a light-sensitive material such as photographic film.

Typically, a lens is used to focus the light reflected or emitted from objects into a real image on the light-sensitive surface inside a camera during a timed exposure. With an electronic image sensor, this produces an electrical charge at each pixel, which is electronically processed and stored in a digital image file for subsequent display or processing. The result with photographic emulsion is an invisible latent image, which is later chemically "developed" into a visible image, either negative or positive depending on the purpose of the photographic material and the method of processing. A negative image on film is traditionally used to photographically create a positive image on a paper base, known as a print, either by using an enlarger or by contact printing.

Science of photography

The science of photography refers to the use of science, such as chemistry and physics, in all aspects of photography. This applies to the camera, its lenses, physical operation of the camera, electronic camera internals, and the process of developing film in order to take and develop pictures properly.

Law of Reciprocity

The law of reciprocity describes how light intensity and duration trade off to make an exposure—it defines the relationship between shutter speed and aperture, for a given total exposure. Changes to any of these elements are often measured in units known as "stops"; a stop is equal to a factor of two.

Halving the amount light exposing the film can be achieved either by:

Likewise, doubling the amount of light exposing the film can be achieved by the opposite of one of these operations.

The luminance of the scene, as measured on a reflected light meter, also affects the exposure proportionately. The amount of light required for proper exposure depends on the film speed; which can be varied in stops or fractions of stops. With either of these changes, the aperture or shutter speed can be adjusted by an equal number of stops to get to a suitable exposure.

Photography (film)

Photography (Hungarian: Fotográfia) is a 1973 Hungarian drama film directed by Pál Zolnay. The film was entered into the 8th Moscow International Film Festival where it won the Silver Prize. It was also selected as the Hungarian entry for the Best Foreign Language Film at the 46th Academy Awards, but was not accepted as a nominee.

Cast

See also

References

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