Camera

A camera is an optical instrument for recording images, which may be stored locally, transmitted to another location, or both. The images may be individual still photographs or sequences of images constituting videos or movies. The word camera comes from camera obscura, which means "dark chamber" and is the Latin name of the original device for projecting an image of external reality onto a flat surface. The modern photographic camera evolved from the camera obscura. The functioning of the camera is very similar to the functioning of the human eye.

Functional description

A camera may work with the light of the visible spectrum or with other portions of the electromagnetic spectrum. A still camera is an optical device which creates a single image of an object or scene, and records it on an electronic sensor or photographic film. All cameras use the same basic design: light enters an enclosed box through a converging lens and an image is recorded on a light-sensitive medium. A shutter mechanism controls the length of time that light can enter the camera. Most photographic cameras have functions that allow a person to view the scene to be recorded, allow for a desired part of the scene to be in focus, and to control the exposure so that it is not too bright or too dim. A display, often a liquid crystal display (LCD), permits the user to view scene to be recorded and settings such as ISO speed, exposure, and shutter speed.

Generic top-level domain

Generic top-level domains (gTLDs) are one of the categories of top-level domains (TLDs) maintained by the Internet Assigned Numbers Authority (IANA) for use in the Domain Name System of the Internet. A top-level domain is the last label of every fully qualified domain name. They are called generic for historic reasons; initially, they were contrasted with country-specific TLDs in RFC 920.

The core group of generic top-level domains consists of the com, info, net, and org domains. In addition, the domains biz, name, and pro are also considered generic; however, these are designated as restricted, because registrations within them require proof of eligibility within the guidelines set for each.

Historically, the group of generic top-level domains included domains, created in the early development of the domain name system, that are now sponsored by designated agencies or organizations and are restricted to specific types of registrants. Thus, domains edu, gov, int, and mil are now considered sponsored top-level domains, much like the themed top-level domains (e.g., jobs). The entire group of domains that do not have a geographic or country designation (see country-code top-level domain) is still often referred to by the term generic TLDs.

Camera (magazine)

Camera is a photography review that began its life in Lucerne, Switzerland, later distributed in many countries and languages. The magazine grew to its greatest international influence towards in latter half of its life of sixty years; on the leading edge of almost every important period in photography, Camera was often among the first publications to show the first works of now well-known photographers such as Edward Steichen, Robert Frank and Jeanloup Sieff. The magazine was slated to be re-launched on17 January 2013.

The early years

The first issue of Camera was published by the engineer Adolf Herz and book-publisher C. J. Bucher in June 1922. The magazine was first published in German. Making clear its aim to aid the development of the still-fledgling art of photography, this issue began with the following statement of intent:

With this issue we introduce ourselves to the public for the first time. We would like to say a few words about our aims. Our magazine will support artistic photography. We thought it expedient to show our readers an artist's work through ample selections of good-quality reproductions. Artists from all countries will be sharing their pictures. Hereon in every issue we will present eight pages of good reproductions. Participating artists will present their art styles in original essays. Articles on technical photographic subjects, written by authors the best in this field, will appear in the technical section. In brief reports we will comment on all new developments so that our readers can obtain an up-to-date view of photography. We invite all photographers and researchers of all countries who would like to bring technical information to our readers, to submit their articles. We will periodically conduct contests to encourage developing artists, and the best entries will receive a monetary award. We hope our efforts will be conducive to the high aims of artistic photography and that our readers will support us.

Ion

An ion (/ˈaɪən, -ɒn/) is an atom or a molecule in which the total number of electrons is not equal to the total number of protons, giving the atom or molecule a net positive or negative electrical charge. Ions can be created, by either chemical or physical means, via ionization.

In chemical terms, if a neutral atom loses one or more electrons, it has a net positive charge and is known as a cation.

If an atom gains electrons, it has a net negative charge and is known as an anion.

An ion consisting of a single atom is an atomic or monatomic ion; if it consists of two or more atoms, it is a molecular or polyatomic ion. Because of their electric charges, cations and anions attract each other and readily form ionic compounds, such as salts.

In the case of physical ionization of a medium, such as a gas, what are known as "ion pairs" are created by ion impact, and each pair consists of a free electron and a positive ion.

History of discovery

The word ion is the Greek ἰόν, ion, "going", the present participle of ἰέναι, ienai, "to go". This term was introduced by English physicist and chemist Michael Faraday in 1834 for the then-unknown species that goes from one electrode to the other through an aqueous medium. Faraday did not know the nature of these species, but he knew that since metals dissolved into and entered a solution at one electrode, and new metal came forth from a solution at the other electrode, that some kind of substance moved through the solution in a current, conveying matter from one place to the other.

Ion (DC Comics)

Ion is a fictional character, a DC Comics superhero. Created by writer Judd Winick and artist Dale Eaglesham for Green Lantern vol. 3 #142, Ion was devised as the new superhero identity for Green Lantern protagonist Kyle Rayner. It was later revealed to be able to form mutualism with a host, bestowing its power to a host willingly. This followed a similar retcon as Parallax, originally the new supervillain alias of Hal Jordan, which was revealed to be a parasitic embodiment of fear in the 2004–2005 miniseries Green Lantern: Rebirth.

Fictional character biography

As soon as sentient beings developed willpower, Ion was born from the green wavelength of the so-called "emotional spectrum". Its existence has been kept a secret for eons, and it resided in the Central Battery on Oa to keep Parallax, the parasitic fear entity also imprisoned there, in check, as well as granting the Guardians of the Universe, Manhunters, The Green Glob, Halla's, and then The Green Lantern Corps a portion of its vast powers. After Hal Jordan, under the influences of Parallax and Sinestro, destroyed the Central Battery, Ion, along with Parallax and Sinestro, were set free. After wandering throughout the cosmos, it eventually settled within Kyle Rayner as its host.

Ion (name)

Ion is a masculine given name. The name form in English corresponds to two different and unrelated names from different original languages.

The first name is the Greek,Ἴων, Iōn, after the mythical founder of the Ionians; the modern (demotic) Greek equivalent of the name is Ionas. The source of this is the Hebrew Yavan, alternatively transliterated as ι-o-ν (Yut Vav/digamma Nun), with each letter corresponding to its appropriate counterpart.

The second name is the Romanian Ion which is equivalent to the English name John and has the same etymology as "Jon", tracing back the Hebrew name Johanan; Ion can also be a surname in Romanian. Another variant is Ioan. A common diminutive is Ionel. Its female form is Ioana. The surname Ionescu derives from Ion.

Ion as a given name