Pinhole camera

A pinhole camera is a simple camera without a lens but with a tiny aperture – a light-proof box with a small hole in one side. Light from a scene passes through the aperture and projects an inverted image on the opposite side of the box, known as the camera obscura effect; the camera obscura or pinhole image is a natural optical phenomenon. Early known descriptions are found in the Aristotelian Problems. A practical demonstration of the pinhole effect from 700 CE is still in existence at the Virupaksha Temple in Hampi, India. Ibn al-Haytham, an Arab physicist known as Alhazen, was the first to study and describe the camera obscura effect. Over the centuries others started to experiment with it in dark rooms with a small opening in shutters to study the nature of light and to safely watch solar eclipses. Giambattista Della Porta wrote in 1558 in his Magia Naturalis about using a convex mirror to project the image onto paper and to use this as a drawing aid. However, about the same time, the use of a lens instead of a pinhole was introduced.

In the 17th century, the camera obscura with a lens became a popular drawing aid, further developed into a mobile device, first in a little tent and in a box. The photographic camera, as developed early in the 19th century, was an adaptation of the box-type camera obscura with a lens; the term "pin-hole" in the context of optics was found in James Ferguson's 1764 book Lectures on select subjects in mechanics, hydrostatics and optics. The first known description of pinhole photography is found in the 1856 book The Stereoscope by Scottish inventor David Brewster, including the description of the idea as "a camera without lenses, with only a pin-hole". Sir William Crookes and William de Wiveleslie Abney were other early photographers to try the pinhole technique. According to inventor William Kennedy Dickson, the first experiments directed at moving pictures by Thomas Edison and his researchers took place around 1887 and involved "microscopic pin-point photographs, placed on a cylindrical shell".

The size of the cylinder corresponded with their phonograph cylinder as they wanted to combine the moving images with sound recordings. Problems arose in recording clear pictures "with phenomenal speed" and the "coarseness" of the photographic emulsion when the pictures were enlarged; the microscopic pin-point photographs were soon abandoned. In 1893 the Kinetoscope was introduced with moving pictures on celluloid film strips; the camera that recorded the images, dubbed Kinetograph, was fitted with a lens. Eugène Estanave experimented with integral photography, exhibiting a result in 1925 and publishing his findings in La Nature. After 1930 he chose to continue his experiments with pinholes replacing the lenticular screen; the image of a pinhole camera may be projected onto a translucent screen for a real-time viewing or to trace the image on paper. But it is more used without a translucent screen for pinhole photography with photographic film or photographic paper placed on the surface opposite to the pinhole aperture.

A common use of pinhole photography is to capture the movement of the sun over a long period of time. This type of photography is called solargraphy. Pinhole photography is used for artistic reasons, but for educational purposes to let pupils learn about, experiment with, the basics of photography. Pinhole cameras with CCDs are sometimes used for surveillance. Related cameras, image forming devices, or developments from it include Franke's widefield pinhole camera, the pinspeck camera, the pinhead mirror. Modern manufacturing has enabled the production of high quality pinhole lenses that can be applied to digital cameras. Pinhole photographs have nearly infinite depth of field, everything appears in focus; as there's no lens distortion, wide-angle images remain rectilinear. Exposure times are long, resulting in motion blur around moving objects and the absence of objects that moved too fast. Other special features can be built into pinhole cameras such as the ability to take double images by using multiple pinholes, or the ability to take pictures in cylindrical or spherical perspective by curving the film plane.

Pinhole cameras can be handmade by the photographer for a particular purpose. In its simplest form, the photographic pinhole camera can consist of a light-tight box with a pinhole in one end, a piece of film or photographic paper wedged or taped into the other end. A flap of cardboard with a tape hinge can be used as a shutter; the pinhole may be punched or drilled using a sewing needle or small diameter bit through a piece of tinfoil or thin aluminium or brass sheet. This piece is taped to the inside of the light-tight box behind a hole cut through the box. A cylindrical oatmeal container may be made into a pinhole camera; the interior of an effective pinhole camera is black to avoid any reflection of the entering light onto the photographic material or viewing screen. Pinhole cameras can be constructed with a sliding film holder or back so the distance between the film and the pinhole can be adjusted; this allows the angle of view of the camera to be changed and the effective f-stop ratio of the camera.

Moving the film closer to the pinhole will result in a wide angle field of view and shorter exposure time. Moving the film farther away from the pinhole will result in a telephoto or narrow-angle view and longer exposure time. Pinhole cameras can be constructed by replacing the lens assembly i

Foundation for Education Support

The Foundation for Education Support is a non-profit government-supported organization created to fund educational programs that promote the cooperation and communication of Russian gimnaziums and secondary schools with leading national universities. Its current major program is the support and development of Gimnazium Union of Russia, an open network or Russian gimnaziums and secondary schools. Andrei Fursenko, the Russian Education Minister introduced the Gimnazium Union of Russia and related projects on November 6, 2007, at a major conference in education held at Saint Petersburg State University; the Foundation was founded and is sponsored by Gazprom. Its activities, such as several introduced National science competitions, are a part of the National Priority Projects and are directly supported by Russian President-elect Dmitry Medvedev and the Russian Ministry of Education. Official website of the Foundation for Education Support Memorandum of Understanding between Russian Education Minister Andrei Fursenko and the Foundation President Tatyana Golubeva.

February 11, 2008. Gimnazium Union unites Russian gymnaziums nationwide. NTV Forum of Gimnanium Union of Russia opened in Saint Petersburg. Rosbalt

Timeline of the Indonesian National Revolution

This is the Timeline of Indonesian National Revolution early 1945: Small Dutch, commando units parachute into northern Sumatra. 15 August: The Japanese surrender brings the fighting in World War II to an official close. 17 August: "Proclamation of Indonesian Independence", signed by Sukarno-Hatta. Tan Malaka, a former Indonesian Communist Party leader, returns secretly from exile and reveals his identity in Jakarta and draws a large following. Late August: A Republican government is established in Jakarta and a provisional constitution is adopted. Central Indonesian National Committee established. 17 to 25 August: The Japanese in Java and Sumatra disband the Peta/Giyugun and Heiho, dismantling command structures and membership. 22 August: The Japanese announce their surrender publicly across Indonesia. August to September: Euphoria of revolution spreads across the country, while local Japanese commanders and their troops abandon urban areas to avoid confrontation. Many discreetly allowed Indonesian youths to acquire arms.

Republican youths take over infrastructure facilities in Jakarta, Surakarta and Bandung with little or no Japanese resistance. Mass pro-Republic rallies are held in Surabaya. Sukarno convinces crowds to disperse without challenging the Japanese, thus further boosting his reputation as the only one able to prevent massive violence. Revolutionary spirit emerges in literature and the arts. September: Brawls break out in Surabaya between Indonesian youths and newly freed Europeans. September: Australian forces accept the Japanese surrender in Japanese Navy area bringing with them Dutch troops and administrators. Early September: Following the August disbanding of the Peta/Giyugun and Heiho, Republican armed forces begin to form from local groups of young men with charisma and/or arms. Early September: Four rulers of the central Javanese principalities declare their support for the Republic. 3 to 11 September: Republican youths take over control of Jakarta railway stations, tram system and radio stations, encountering little Japanese resistance.

11 and 17 September: Mass pro-Republic rallies held in Surabaya. Mid September: News of the proclamation of independence reaches all outer islands. 19 September: Pro-Republic rally of an estimated 200,000 people gathered by Tan Malaka is held in Jakarta in what is now known as Merdeka Square. Fearing violent confrontations with the Japanese, Sukarno manages to convince the crowd to disperse. Mid-September to mid-October: Australian troops occupy the major cities of eastern Indonesia—in most cases before Republican administrations have been established—putting down demonstrations and arresting some pro-Republican officials. Pro-Republican rajas of southern Sulawesi decide against fighting the Australians and begrudgingly accept the return of the Dutch. Late September: British troops Indian, reach Jakarta. Late September: Major public infrastructure in Yogyakarta, Surakarta and Bandung is now controlled by Republican youths. Late September: News of the proclamation of Indonesian independence has now spread to all outer islands.

October: The Communist Party of Indonesia is reconstituted after its 1920's disbanding. October: The beginnings of the so-called'three regions affair' on the north coast of Java. Actions are underway by both young Orthodox Muslim activists and survivors of the 1926 PKI uprising against village headsmen. October: British troops Indian, arrive in Medan, Palembang and Surabaya. To avoid confrontation, British commander Lieutenant General Sir Philip Christion, diverts soldiers of former Dutch East Indies army from Java to eastern Indonesia, where Dutch re-occupation was proceeding smoothly, there was considerable economic value. October: Tensions mount in Java and Sumatra where street fights develop between young Republicans on the one hand, former Dutch prisoners, Dutch colonial troops, Indo-Europeans and Japanese on the other. October: The Japanese attempt to recover authority in Javan cities, which they had ceded in August and September, triggering the first stages of warfare. 3 October: Japanese Military Police massacre Republican pemuda in Pekalongan.

3 October: After providing Indonesians ready access to arms, the pro-Republic Japanese commander in Surabaya, Vice-Admiral Shibata Yaichiro, surrenders to the first Allied representative, a Dutch navy captain. 5 October: The nucleus of the Indonesian National Armed Forces, the Public Security Armed Forces, is formed on the basis of the units of the People's Security Department. 10 October: Japanese troops push Republicans out of Bandung and a week hand the city over to the British. 1945, 14 October: Japanese troops begin to reclaim Semarang. Republicans retaliate by killing between 300 Japanese-held prisoners. 16 October: Sutan Sjahrir and Amir Sjarifuddin engineer a takeover within the KNIP. Late October to early November: Leaders of Nahdlatul Ulama and Masyumi declare that war in defence of the Indonesian fatherland is Holy War, an obligation laid upon all Muslims. Muslims students begin to pour into Surabaya; the fiery Sutomo, uses the local radio to encourage an atmosphere of fanatical revolutionary enthusiasm throughout the city 20 October: Japanese have won Semarang but 500 Japanese and 2,000 Indonesians are killed.

British troops arrive in Semarang. Late October: British attempt to evacuate Eurasians and Europeans from volatile inland central Java. British detachments are