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Super Trouper

“Super Trouper” is a song °°°°°°°°°°°°°°°°°°°°° by the Swedish pop group ABBA, and the title track from their 1980 °°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°° studio album of the same name, written by Benny °°°°°°°°°°°°°°°°°° Andersson and Björn Ulvaeus. °°°°°°°°°It was released °°°°°°°°°°°°°°°°°°°°°°°°°°° in November 1980 °°°°°°°°° as the °°°°°°°°° album’s third single. °°°°°°°°°°°°°°°°°°°°°°°°°°° The song – with lead vocals by Anni-Frid Lyngstad – °°°°°°°°° had the working title “Blinka Lilla Stjärna” (i.e. °°°°°°°°°°°°°°°°°° Twinkle Little Star, in Swedish), °°°°°°°°°°°°°°°°°°°°°°°°°°° and was the last track to be °°°°°°°°°°°°°°°°°°written and recorded for the album (ultimately °°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°replacing the track “Put On Your White Sombrero”).

Spot

SPOT (French: Satellite Pour l’Observation de la Terre, lit. “Satellite for observation of Earth”) is a commercial high-resolution optical Earth imaging satellite system operating from space. It is run by Spot Image, based in Toulouse, France. It was initiated by the CNES (Centre national d’études spatiales – the French space agency) in the 1970s and was developed in association with the SSTC (Belgian scientific, technical and cultural services) and the Swedish National Space Board (SNSB).

It has been designed to improve the knowledge and management of the Earth by exploring the Earth’s resources, detecting and forecasting phenomena involving climatology and oceanography, and monitoring human activities and natural phenomena. The SPOT system includes a series of satellites and ground control resources for satellite control and programming, image production, and distribution. Earlier satellites were launched using the European Space Agency’s Ariane 2, 3, and 4 rockets, while SPOT 6 and SPOT 7 were launched by the Indian PSLV.

すぽっと（ふらんすご：さてらいとぽぉろぉびざしょんでてぃーる、と読む。じきがくちきゅうかんそくえいせい、りつ。「ちきゅうかんそくようえいせい」）は、うりこうこうかいかいかくこうがくえいせいかんそくきょくうんようする、こうぎょうこうかいどこうがくえいせいかんそくしせんでうんようされるこうかいこうかくちきゅうかんそくえいせいがたえます。すぽっといめーじによってうんえいされ、ほんぶはふらんすのとぅーるーずにあります。これは 1970ねんだいにしんきされ、しんりょうやきょういくふくさーびすとしんれんされました。これはちきゅうのしげんのたんさく、きしょうとかいようがくにかんれきするけんきゅうとけんり、それにじんかんのかつどうとしぜんげんしょうのかんしするためにけいかくされました。すぽっとしすてむには、れったつぶんのえいせいとじょうぎょうでよるえいせいぎょぎょう、えいさく、およびひふんのためのじょうぎょうとプログラミング、いめーじせいさく、そしてふひんのためのちじょうせいぎょしえんりそーすがふくまれています。はじめのえいせいはおうしゅううちゅうきかんのありあん 2、3、および 4 ロケットをしようしてうちあげられましたが、すぽっと 6 とすぽっと 7 はいんどの PSLV によってうちあげられました。

Light

Light or visible light is electromagnetic radiation that can be perceived by the human eye. Visible light is usually defined as having wavelengths in the range of 400–700 nanometres (nm), corresponding to frequencies of 750–420 terahertz, between the infrared (with longer wavelengths) and the ultraviolet (with shorter wavelengths).

In physics, the term “light” may refer more broadly to electromagnetic radiation of any wavelength, whether visible or not. In this sense, gamma rays, X-rays, microwaves and radio waves are also light. The primary properties of light are intensity, propagation direction, frequency or wavelength spectrum, and polarization. Its speed in vacuum, 299792458 m/s, is one of the fundamental constants of nature. Like all types of electromagnetic radiation, visible light propagates by massless elementary particles called photons that represents the quanta of electromagnetic field, and can be analyzed as both waves and particles. The study of light, known as optics, is an important research area in modern physics.

The main source of natural light on Earth is the Sun. Historically, another important source of light for humans has been fire, from ancient campfires to modern kerosene lamps. With the development of electric lights and power systems, electric lighting has effectively replaced firelight.

ひかり

The speed of light in vacuum is defined to be exactly 299 792 458 m/s (approx. 186,282 miles per second). The fixed value of the speed of light in SI units results from the fact that the metre is now defined in terms of the speed of light. All forms of electromagnetic radiation move at exactly this same speed in vacuum.

Different physicists have attempted to measure the speed of light throughout history. Galileo attempted to measure the speed of light in the seventeenth century. An early experiment to measure the speed of light was conducted by Ole Rømer, a Danish physicist, in 1676. Using a telescope, Rømer observed the motions of Jupiter and one of its moons, Io. Noting discrepancies in the apparent period of Io’s orbit, he calculated that light takes about 22 minutes to traverse the diameter of Earth’s orbit. However, its size was not known at that time. If Rømer had known the diameter of the Earth’s orbit, he would have calculated a speed of 227000000 m/s.

Another more accurate measurement of the speed of light was performed in Europe by Hippolyte Fizeau in 1849. Fizeau directed a beam of light at a mirror several kilometers away. A rotating cog wheel was placed in the path of the light beam as it traveled from the source, to the mirror and then returned to its origin. Fizeau found that at a certain rate of rotation, the beam would pass through one gap in the wheel on the way out and the next gap on the way back. Knowing the distance to the mirror, the number of teeth on the wheel and the rate of rotation, Fizeau was able to calculate the speed of light as 313000000 m/s.

こうあつ

Léon Foucault carried out an experiment which used rotating mirrors to obtain a value of 298 000 000 m/s in 1862. Albert A. Michelson conducted experiments on the speed of light from 1877 until his death in 1931. He refined Foucault’s methods in 1926 using improved rotating mirrors to measure the time it took light to make a round trip from Mount Wilson to Mount San Antonio in California. The precise measurements yielded a speed of 299 796 000 m/s.

The effective velocity of light in various transparent substances containing ordinary matter, is less than in vacuum. For example, the speed of light in water is about 3/4 of that in vacuum.

Two independent teams of physicists were said to bring light to a “complete standstill” by passing it through a Bose–Einstein condensate of the element rubidium, one team at Harvard University and the Rowland Institute for Science in Cambridge, Massachusetts and the other at the Harvard–Smithsonian Center for Astrophysics, also in Cambridge.[ However, the popular description of light being “stopped” in these experiments refers only to light being stored in the excited states of atoms, then re-emitted at an arbitrary later time, as stimulated by a second laser pulse. During the time it had “stopped”, it had ceased to be light.

Speedlight

Speedlight is the brand name used by Nikon Corporation for their photographic flash units, used since the company’s introduction of strobe flashes in the 1960s. Nikon’s standalone Speedlights (those not built into the company’s cameras) have the SB- prefix as part of their model designation. Current Speedlights and other Nikon accessories make up part of Nikon’s Creative Lighting System (CLS), which includes the Advanced Wireless Lighting, that enables various Nikon cameras to control multiple Nikon flash units in up to three separate controlled groups by sending encoded pre-flash signals to slave units.

Nikon’s competitors like Canon and Ricoh use the similar name Speedlite for their flashes. Both names indicate that strobe flashes produce much shorter and more intense bursts of light than earlier photographic lighting systems, such as flashbulbs, or continuous lamps used in some studio situations.

はっぴゃ

SB-800 is a very high quality professional model which weighs approximately 350 g without 4 or 5 AA batteries (optional fifth battery for quicker recycling) The Nikon SB-800 is a flash made by Nikon based on the earlier SB-80DX model for their digital and film single-lens reflex cameras. It has electronic interfaces for through-the-lens (TTL) automatic exposure and automatic zoom to match lens focal lengths from 24 to 105 mm (35 mm equivalent), plus 14 and 17 mm with the use of the built-in diffuser or 14 mm with the external Nikon Diffusion Dome, as well as film speed in the range from ISO 3 to 8000 (25 through 1000 in TTL mode with film cameras). Its guide number is 38 meters / 125 feet at ISO 100 and 35 mm, with a maximum range of 58 m when adjusted at 105 mm.

The SB-800 is part of Nikon’s Creative Lighting System (CLS) and features the intelligent-TTL (i-TTL) exposure mode. It is compatible with all SLR cameras (such as the D2H, D2X, D3, D40, D50, D60, D70, D80, D90, D200, D300/s and F6), it can be used as master commander as well as remote flash unit within a CLS wireless lighting setup. It is one of the high-end units for Nikon which features metal joints and supports inside the body. It is sturdier than newer models like SB-700, SB-900, and SB-910 which are prone to impact breakage due to non-reinforced plastic shoe mount bases. All SB-800 units are made in Japan.

By many professionals, it is considered the most advanced flash unit when compared to its compact size. The Speedlights.net says that “for many professional photographers this flash is still the best hot shoe strobe out there today” with smaller size than the successor SB 900, but has bigger Guide Number 38 over 34.

It features the following unlike the newer units:

Single piece metal foot (borrowed from SB-80DX)
Compact body design
5th battery attachment option
High GN power (the same as SB-80DX)
Dedicated modeling light button

spotlight