1.
Photography
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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 sensor, this produces an electrical charge at each pixel. A negative image on film is used to photographically create a positive image on a paper base, known as a print. The word photography was created from the Greek roots φωτός, genitive of φῶς, light and γραφή representation by means of lines or drawing, several people may have coined the same new term from these roots independently. Johann von Maedler, a Berlin astronomer, is credited in a 1932 German history of photography as having used it in an article published on 25 February 1839 in the German newspaper Vossische Zeitung. Both of these claims are now widely reported but apparently neither has ever been confirmed as beyond reasonable doubt. Credit has traditionally given to Sir John Herschel both for coining the word and for introducing it to the public. Photography is the result of combining several technical discoveries, later Greek mathematicians Aristotle and Euclid also independently described a pinhole camera in the 5th and 4th centuries BCE. Daniele Barbaro described a diaphragm in 1566, wilhelm Homberg described how light darkened some chemicals in 1694. The fiction book Giphantie, published in 1760, by French author Tiphaigne de la Roche, the discovery of the camera obscura that provides an image of a scene dates back to ancient China. Leonardo da Vinci mentions natural camera obscura that are formed by dark caves on the edge of a sunlit valley, a hole in the cave wall will act as a pinhole camera and project a laterally reversed, upside down image on a piece of paper. So the birth of photography was primarily concerned with inventing means to capture, renaissance painters used the camera obscura which, in fact, gives the optical rendering in color that dominates Western Art. The camera obscura literally means dark chamber in Latin and it is a box with a hole in it which allows light to go through and create an image onto the piece of paper. Around the year 1800, British inventor Thomas Wedgwood made the first known attempt to capture the image in a camera obscura by means of a light-sensitive substance and he used paper or white leather treated with silver nitrate. The shadow images eventually darkened all over, the first permanent photoetching was an image produced in 1822 by the French inventor Nicéphore Niépce, but it was destroyed in a later attempt to make prints from it. Niépce was successful again in 1825, in 1826 or 1827, he made the View from the Window at Le Gras, the earliest surviving photograph from nature. Because Niépces camera photographs required a long exposure, he sought to greatly improve his bitumen process or replace it with one that was more practical. With an eye to eventual commercial exploitation, the partners opted for total secrecy, Daguerres efforts culminated in what would later be named the daguerreotype process
2.
Wildlife
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Wildlife traditionally refers to undomesticated animal species, but has come to include all plants, fungi, and other organisms that grow or live wild in an area without being introduced by humans. Wildlife can be found in all ecosystems, humans have historically tended to separate civilization from wildlife in a number of ways including the legal, social, and moral sense. Some animals, however, have adapted to suburban environments and this includes such animals as domesticated cats, dogs, mice, and gerbils. The global wildlife population has decreased by 52 percent between 1970 and 2014, according to a report by the World Wildlife Fund, anthropologists believe that the Stone Age people and hunter-gatherers relied on wildlife, both plants and animals, for their food. In fact, some species may have been hunted to extinction by human hunters. Today, hunting, fishing, and gathering wildlife is still a significant food source in parts of the world. In other areas, hunting and non-commercial fishing are seen as a sport or recreation. Meat sourced from wildlife that is not traditionally regarded as game is known as bush meat, in November 2008, almost 900 plucked and oven-ready owls and other protected wildlife species were confiscated by the Department of Wildlife and National Parks in Malaysia, according to TRAFFIC. The animals were believed to be bound for China, to be sold in wild meat restaurants, most are listed in CITES which prohibits or restricts such trade.60. Many Amazon species, including peccaries, agoutis, turtles, turtle eggs, anacondas, armadillos, others in these informal markets, such as monkeys and parrots, are destined for the pet trade, often smuggled into the United States. Still other Amazon species are popular ingredients in traditional medicines sold in local markets, the medicinal value of animal parts is based largely on superstition. Many animal species have spiritual significance in different cultures around the world, for example, eagles, hawks and their feathers have great cultural and spiritual value to Native Americans as religious objects. In Hinduism the cow is regarded sacred, muslims conduct sacrifices on Eid-ul-Adha to commemorate the sacrificial spirit of Ibrahim in love of God. Camels, sheep, goats, and cows may be offered as sacrifice during the three days of Eid, many nations have established their tourism sector around their natural wildlife. South Africa has, for example, many opportunities for tourists to see the wildlife in its national parks. In South India the Periar Wildlife Sanctuary, Bandipur National Park and Mudamalai Wildlife Sanctuary are situated around, India is home to many national parks and wildlife sanctuaries showing the diversity of its wildlife, much of its unique fauna, and excels in the range. This subsection focuses on forms of wildlife destruction. Exploitation of wild populations has been a characteristic of man since our exodus from Africa 130,000 –70,000 years ago
3.
Ethology
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Ethology is the scientific and objective study of animal behaviour, usually with a focus on behaviour under natural conditions, and viewing behaviour as an evolutionarily adaptive trait. Many naturalists have studied aspects of animal behaviour throughout history, Ethology is a combination of laboratory and field science, with a strong relation to some other disciplines such as neuroanatomy, ecology, and evolutionary biology. Ethologists are typically interested in a process rather than in a particular animal group. Ethology is a growing field. New fields, such as neuroethology, have developed, understanding ethology or animal behaviour can be important in animal training. Considering the natural behaviours of different species or breeds enables the trainer to select the individuals best suited to perform the required task and it also enables the trainer to encourage the performance of naturally occurring behaviours and also the discontinuance of undesirable behaviours. The term ethology derives from the Greek language, ἦθος, ethos meaning character and -λογία, the term was first popularized by American myrmecologist William Morton Wheeler in 1902. An earlier, slightly different sense of the term was proposed by John Stuart Mill in his 1843 System of Logic. He recommended the development of a new science, ethology, the purpose of which would be explanation of individual and national differences in character and this use of the word was never adopted. Comparative psychology also studies animal behaviour, but, as opposed to ethology, is construed as a sub-topic of psychology rather than as one of biology. The two approaches are complementary rather than competitive, but they do result in different perspectives, in addition, for most of the twentieth century, comparative psychology developed most strongly in North America, while ethology was stronger in Europe. From a practical standpoint, early comparative psychologists concentrated on gaining extensive knowledge of the behaviour of very few species, ethologists were more interested in understanding behaviour across a wide range of species to facilitate principled comparisons across taxonomic groups. Ethologists have made more use of such cross-species comparisons than comparative psychologists have. See also, Great Chain of Being Until the 19th century, jean-Baptiste Lamarck was the first biologist to describe a complex theory of evolution. The second statement is that living organism, humans included. When Charles Darwin went to the Galapagos Islands, he was aware of Lamarcks theories and was influenced by them. In one sense, the first modern ethologist was Charles Darwin, whose book The Expression of the Emotions in Man, other early ethologists, such as Charles O. Their beginning for studying the behaviour of a new species was to construct an ethogram and this provided an objective, cumulative data-base of behaviour, which subsequent researchers could check and supplement
4.
Game stalker
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Defined narrowly, a game stalker is a hunter who for sport, approaches close to its timid quarry before making a kill. The practice is associated with the moors of Scotland where the principal quarry is red deer. However, the skill is found worldwide and is of long standing. Many other species such as cats and hyenas also stalk their prey, among hunter-gatherers, where their quarry is timid, stalking is a way of livelihood in order that they may catch what they hunt. Nowadays, stalking is frequently done for purposes of photography or observation of animal behaviour rather than for killing, whatever the means of killing, the hunter has to be near the quarry in order to achieve it. Most animals are sensitive to the presence of predators. In many cases, their sense of smell is highly developed, the stalker therefore needs to approach from down-wind. Similarly, care needs to be taken to avoid being seen, in North America the term still hunting describes an immobile technique distinct from stalking. The deerstalker is a type of hat associated with Sherlock Holmes, notable for its slight rain-brim to the front and back, with a camouflage checked twill pattern and fold-down earpieces for selective warmth or to raise when listening for deer
5.
Lens speed
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Lens speed refers to the maximum aperture diameter, or minimum f-number, of a photographic lens. Lenses may also be referred to as being faster or slower than one another, with 35mm cameras, the fastest lenses are typically in the normal lens range near 50mm and there are several high-quality fast lenses available that are relatively inexpensive. For example, the Canon EF 50mm f/1.8 II or Nikon AF Nikkor 50mm f/1. 8D are very inexpensive, but quite fast and optically well-regarded. Old fast manual focus lenses, just as the Nikkor-S or Nikkor AI-S 50mm f/1.4, were historically produced abundantly, especially outside of the normal lenses, lens speed also tends to correlate with the price and/or quality of the lens. This is because lenses with maximum apertures require greater care with regard to design, precision of manufacture, special coatings. At wide apertures, spherical aberration becomes significant and must be corrected. Faster telephoto and wide-angle retrofocus designs tend to be more expensive. The fastest lenses in production now are f/1.2 or f/1.4, with more at f/1.8 and f/2.0. For example, the 1911 Encyclopædia Britannica states that. For scale, note that f/0.5, f/0.7, f/1.0, f/1.4, and f/2.0 are each 1 f-stop apart, as an f-stop corresponds to a factor of square root of 2, about 1.4. Thus around f/1.0, a change of 0.1 corresponds to about 1/4 of an f-stop, f/1.0 is about 50% faster than f/1.2, which is about 50% faster than f/1.4. As of 2012, Canon, Nikon, Pentax and Sony all make an autofocus 50mm f/1.4 lens and these are not unusual lenses and are relatively inexpensive. Canon also makes autofocus 50mm and 85mm f/1.2 lenses, while Nikon makes a manual focus 50mm f/1.2 lens, Pentax makes a 50mm f/1.4 lens and 55mm f/1.4 lens for APS-C cameras, see Pentax lenses. Sony makes a 50mm f/1.4 lens which is a continuation of the Minolta AF 50mm f/1.4 lens, the maximum exposure time in free-hand photography can be enhanced even more also for fast lenses, if the camera is equipped with an image stabilisation system. In the mid 60s there was something of a fad for fast lenses among the major manufacturers, in 1966 in response to the trend Carl Zeiss displayed a prop lens christened the Super-Q-Gigantar 40mm f/0.33 at photokina. Made from various parts found around the factory the claimed speed and focal lengths were purely nominal, ultimately, the speed of a lens is limited by mechanical constraints of the camera system. This sets a limit close to f/1.0 to f/1.2 for most SLR mounts, whereas lenses for rangefinder and mirrorless cameras can be faster, as they can be brought closer to the image plane. Reproduction lenses incapable of infinity focus can have nominal f-numbers smaller than this limit, as the limit applies to the working f-number and it should be noted that only the working f-number correctly assesses the light gathering power of the lens
6.
Camera lens
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A lens might be permanently fixed to a camera, or it might be interchangeable with lenses of different focal lengths, apertures, and other properties. While in principle a simple convex lens will suffice, in practice a compound made up of a number of optical lens elements is required to correct the many optical aberrations that arise. Some aberrations will be present in any lens system and it is the job of the lens designer to balance these and produce a design that is suitable for photographic use and possibly mass production. Typical rectilinear lenses can be thought of as improved pinhole lenses, as shown, a pinhole lens is simply a small aperture that blocks most rays of light, ideally selecting one ray to the object for each point on the image sensor. Here a pixel is the area of the detector exposed to light from a point on the object, making the pinhole smaller improves resolution, but reduces the amount of light captured. At a certain point, shrinking the hole does not improve the resolution because of the diffraction limit, beyond this limit, making the hole smaller makes the image blurrier as well as darker. Practical lenses can be thought of as an answer to the question how can a pinhole lens be modified to more light. A first step is to put a simple convex lens at the pinhole with a length equal to the distance to the film plane. The geometry is almost the same as with a pinhole lens. From the front of the camera, the hole, would be seen. If one were inside the camera, one would see the acting as a projector. The virtual image of the aperture from inside the camera is the exit pupil. Practical photographic lenses include more lens elements, a camera lens may be made from a number of elements, from one, as in the Box Brownies meniscus lens, to over 20 in the more complex zooms. These elements may themselves comprise a group of lenses cemented together, the front element is critical to the performance of the whole assembly. In all modern lenses the surface is coated to reduce abrasion, flare, and surface reflectance, to minimize aberration, the curvature is usually set so that the angle of incidence and the angle of refraction are equal. In a prime lens this is easy, but in a zoom there is always a compromise, the lens usually is focused by adjusting the distance from the lens assembly to the image plane, or by moving elements of the lens assembly. To improve performance, some lenses have a cam system that adjusts the distance between the groups as the lens is focused, manufacturers call this different things, Nikon calls it CRC, Canon calls it a floating system, and Hasselblad and Mamiya call it FLE. Glass is the most common used to construct lens elements, due to its good optical properties
7.
Film speed
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Film speed is the measure of a photographic films sensitivity to light, determined by sensitometry and measured on various numerical scales, the most recent being the ISO system. A closely related ISO system is used to measure the sensitivity of digital imaging systems, highly sensitive films are correspondingly termed fast films. In both digital and film photography, the reduction of exposure corresponding to use of higher sensitivities generally leads to reduced image quality, in short, the higher the sensitivity, the grainier the image will be. Ultimately sensitivity is limited by the efficiency of the film or sensor. The speed of the emulsion was then expressed in degrees Warnerke corresponding with the last number visible on the plate after development. Each number represented an increase of 1/3 in speed, typical speeds were between 10° and 25° Warnerke at the time. The concept, however, was built upon in 1900 by Henry Chapman Jones in the development of his plate tester. In their system, speed numbers were inversely proportional to the exposure required, for example, an emulsion rated at 250 H&D would require ten times the exposure of an emulsion rated at 2500 H&D. The methods to determine the sensitivity were later modified in 1925, the H&D system was officially accepted as a standard in the former Soviet Union from 1928 until September 1951, when it was superseded by GOST 2817-50. The Scheinergrade system was devised by the German astronomer Julius Scheiner in 1894 originally as a method of comparing the speeds of plates used for astronomical photography, Scheiners system rated the speed of a plate by the least exposure to produce a visible darkening upon development. ≈2 The system was extended to cover larger ranges and some of its practical shortcomings were addressed by the Austrian scientist Josef Maria Eder. Scheiners system was abandoned in Germany, when the standardized DIN system was introduced in 1934. In various forms, it continued to be in use in other countries for some time. The DIN system, officially DIN standard 4512 by Deutsches Institut für Normung, was published in January 1934, International Congress of Photography held in Dresden from August 3 to 8,1931. The DIN system was inspired by Scheiners system, but the sensitivities were represented as the base 10 logarithm of the sensitivity multiplied by 10, similar to decibels. Thus an increase of 20° represented an increase in sensitivity. ≈3 /10 As in the Scheiner system, speeds were expressed in degrees, originally the sensitivity was written as a fraction with tenths, where the resultant value 1.8 represented the relative base 10 logarithm of the speed. Tenths were later abandoned with DIN4512, 1957-11, and the example above would be written as 18° DIN, the degree symbol was finally dropped with DIN4512, 1961-10
8.
Quagga
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The quagga is an extinct subspecies of plains zebra that lived in South Africa until the 19th century. It was long thought to be a species, but genetic studies have shown it to be the southernmost subspecies of plains zebra. It is considered close to Burchells zebra. Its name was derived from its call, which sounded like kwa-ha-ha, the quagga is believed to have been around 257 cm long and 125–135 cm tall at the shoulder. It was distinguished from other zebras by its pattern of primarily brown and white stripes. The rear was brown and without stripes, and therefore more horse-like, the distribution of stripes varied considerably between individuals. Little is known about the behaviour, but it may have gathered into herds of 30–50 individuals. Quaggas were said to be wild and lively, yet were also considered more docile than Burchells zebra and they were once found in great numbers in the Karoo of Cape Province and the southern part of the Orange Free State in South Africa. After the Dutch settlement of South Africa began, the quagga was hunted as it competed with domesticated animals for forage. While some individuals were taken to zoos in Europe, breeding programs were unsuccessful, the last wild population lived in the Orange Free State, and the quagga was extinct in the wild by 1878. The last captive died in Amsterdam on 12 August 1883. Only one quagga was ever photographed alive and only 23 skins are preserved today, the name quagga is derived from the Khoikhoi word for zebra and is onomatopoeic, being said to resemble the quaggas call, variously transcribed as kwa-ha-ha, kwahaah, or oug-ga. The name is used colloquially for the plains zebra. The quagga was originally classified as a species, Equus quagga. Traditionally, the quagga and the plains and mountain zebras were placed in the subgenus Hippotigris. There has been debate over the status of the quagga in relation to the plains zebra. It is poorly represented in the record, and the identification of these fossils is uncertain. Quaggas have also identified in cave art attributed to the San
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