We are living in an age of scientific progress. In our generation we have seen achieve some things that our forefathers considered impossible.The pace at which science is progressing is perpetually accelerating. It has been estimated that the entire scientific knowledge that man had acquired from the time of his creation to 1750 A.D. was doubled all of a sudden within a period of 150 years by 1900 A.D. The knowledge that was man's by 1900 A.D. doubled again and this time in just 50 years - by 1950 A.D. This knowledge doubled again in just 10 years - by 1960. It has been estimated that man's scientific knowledge has been doubling thereafter every two and
half years. Take for instance the speed of travel, as one indication of scientific advance. 200 years ago man traveled on horseback just like his primitive ancestors did thousands of years
earlier. But by 1900, man could travel by advanced means of locomotion at about 80 kilometres per hour and this was considered a very fast speed in those days. By 1945, jet planes had come into the air and man was traveling at 1000 kmph. Today, man travels in space at over 40,000 kmph. We say that space has been conquered because man has reached the moon; but we must
not forget that the moon is just on the fringe of space. Space itself is so vast that it staggers our imagination. Let's have a look at the universe and at space! The average distance of the moon from the earth is about 400,000 kilometres. This is very small compared with the distance from the earth to the sun which is about 150 million kilometres. The distance of the sun looks quite considerable, but is actually quite negligible when compared with the distance of the nearest star. When calculating distances to the stars, ordinary units of measurement will not do, for
they lead us into fantastically large figures. Scientists and astronomers therefore use the "light year" as the unit of measurement - that is, the distance that light travels in one year. Remember that light travels about 300,000 kilometres (or 7 times around the earth) in one second. So the distance that it travels in one year comes to over 9000 billion kilometres. Let us consider the distances to some of the stars. The nearest star visible to the naked eye is a star called "Alpha Centauri" - which is four and a half light years away - that is, about 250,000 times the distance to the sun. This means that if you traveled at the speed of light, even though you would reach the moon in one and a half seconds and the sun in eight and a half minutes you would have to travel for four and a half years at that speed to reach "Alpha Centauri." To get a better idea of what this means, consider a scale model of the universe where the earth is represented by a grain of sand and the sun by a marble, 3 feet away from the earth. All the planets of our solar system would then come within a radius of 100 feet from the sun. But the nearest star would be 150 miles away from the earth on that scale model of the universe. The farthest star visible to the naked eye is in the Andromeda Galaxy, which is more than 1.5 million light years away. There are still more distant galaxies that are visible through telescopes, 6,500 million light years away. Now look at the sizes of some of the stars. They look so small that little children say
"Twinkle, twinkle little star". The earth looks pretty large! It takes us many hours to get from one place to another on this earth. But the sun is so large that 1 million spheres the size of the earth could fit into it, if it were hollow. Yet even the sun is small compared to some stars. Some stars are so large that 500 million spheres the size of the sun could fit inside each of them if they were hollow. The star Betelgeuse, 520 light years from the earth, is one of the bright stars of the Orion belt. Its diameter is 500 million kilometres - which means that if it were hollow, the earth
could comfortably revolve around the sun, INSIDE THIS STAR, in its normal orbit! (The earth's orbit around the sun being only 300 million kilometres in diameter). Now consider the number of the stars. Our solar system is part of a galaxy called the "Milky Way". Astronomers have estimated that there are at least 100,000 million stars in this galaxy. The sun is just one such star. And the Milky way is just one galaxy among many. Astronomers tell us that there are at least 100 million galaxies in the part of space that telescopes can see. There are many more beyond. Consider too the perfect precision with which these heavenly bodies move in their orbits. The best man-made watch is not more precise than the stars in the heavens. Surely there must be a Supreme Intelligence behind this universe, that created and planned each star and planet. How vast is space! How small is man! One of the writers in the Bible wrote thus, "When
I look up into the night skies and see the stars, I can't understand oh God why you should pay any attention to puny man". Yet, God the creator of this universe cares for each of us. This is the marvelous truth we learn in the Bible. The value of any article is not determined by its size. A millionaire may own acres of land. But his little child is more precious to him than all those large tracts of land. So with God. Space may be vast. The stars may be huge in their size. But God loves and cherishes man more than all of His creation. Man was created to be a son of God, to have fellowship with God. It is such a fellowship with God alone that can give meaning and
purpose to man's existence. We can see the greatness of God in creation. But the Bible reveals that this God is also One who loves us and cares for us.
Saturday, October 17, 2009
Photography
The word photography derives from the Greek words 'photos' - meaning light and 'graphein' - to write. The word was popularised by Sir John Herschel in 1839. Modern photography began in the 1820s with the first permanent photographs.
A camera obscura box used for drawing images
Photography is the result of combining several technical discoveries. Long before the first photographs were made, Chinese philosopher Mo Ti and Greek philosophers such as Aristotle and Euclid described a pinhole camera in the 5th and 4th centuries B.C.E,[2][3] Ibn al-Haytham (Alhazen) (965–1040) studied the camera obscura and pinhole camera,[3][4] Albertus Magnus (1193/1206-1280) discovered silver nitrate, and Georges Fabricius (1516-1571) discovered silver chloride. Daniel Barbaro described a diaphragm in 1568. Wilhelm Homberg described how light darkened some chemicals (photochemical effect) in 1694. The novel Giphantie (by the French Tiphaigne de la Roche, 1729-1774) described what can be interpreted as photography.
For years images have been projected onto surfaces. According to the Hockney–Falco thesis as argued by artist David Hockney,[5] some artists used the camera obscura and camera lucida to trace scenes as early as the 16th century. However, this theory is heavily disputed by today's contemporary realist artists who are able to create high levels of realism without optical aids.[6] These early cameras did not record an image, but only projected images from an opening in the wall of a darkened room onto a surface, turning the room into a large pinhole camera. The phrase camera obscura literally means dark chamber. While this early prototype of today's modern camera may have had modest usage in its time, it was an important step in the evolution of the invention.
Development of chemical photography
The first permanent photograph was an image produced in 1825 by the French inventor Joseph Nicéphore Niépce. His photographs were produced on a polished pewter plate covered with a petroleum derivative called bitumen of Judea. Bitumen hardens with exposure to light. The unhardened material may then be washed away and the metal plate polished, rendering a negative image which then may be coated with ink and impressed upon paper, producing a print. Niépce then began experimenting with silver compounds based on a Johann Heinrich Schultz discovery in 1724 that a silver and chalk mixture darkens when exposed to light.
In partnership, Niépce (in Chalon-sur-Saône) and Louis Daguerre (in Paris) refined the existing silver process.[7] In 1833 Niépce died of a stroke, leaving his notes to Daguerre. While he had no scientific background, Daguerre made two pivotal contributions to the process. He discovered that exposing the silver first to iodine vapour before exposure to light, and then to mercury fumes after the photograph was taken, could form a latent image. Bathing the plate in a salt bath then fixes the image. On January 7, 1839 Daguerre announced that he had invented a process using silver on a copper plate called the daguerreotype.[8] The French government bought the patent and immediately made it public domain.
In 1832, French-Brazilian painter and inventor Hercules Florence had already created a very similar process, naming it Photographie.
After reading about Daguerre's invention, Fox Talbot worked on perfecting his own process; in 1839 he got a key improvement, an effective fixer, from John Herschel, the astronomer, who had previously showed that hyposulfite of soda (also known as hypo, or now sodium thiosulfate) would dissolve silver salts. Later that year, Herschel made the first glass negative.
By 1840, Talbot had invented the calotype process. He coated paper sheets with silver chloride to create an intermediate negative image. Unlike a daguerreotype, a calotype negative could be used to reproduce positive prints, like most chemical films do today. Talbot patented[9] this process, which greatly limited its adoption. He spent the rest of his life in lawsuits defending the patent until he gave up on photography. Later George Eastman refined Talbot's process, which is the basic technology used by chemical film cameras today. Hippolyte Bayard had also developed a method of photography but delayed announcing it, and so was not recognized as its inventor.
In 1851 Frederick Scott Archer invented the collodion process.[citation needed] Photographer and children's author Lewis Carroll used this process.[citation needed]
Slovene Janez Puhar invented the technical procedure for making photographs on glass in 1841.[citation needed] The invention was recognized on July 17, 1852 in Paris by the Académie Nationale Agricole, Manufacturière et Commerciale.
Roger Fenton's assistant seated on Fenton's photographic van, Crimea, 1855.
Herbert Bowyer Berkeley experimented with his own version of collodian emulsions after Samman introduced the idea of adding dithionite to the pyrogallol developer.[citation needed] Berkeley discovered that with his own addition of sulfite, to absorb the sulfur dioxide given off by the chemical dithionite in the developer, that dithionite was not required in the developing process. In 1881 he published his discovery. Berkeley's formula contained pyrogallol, sulfite and citric acid. Ammonia was added just before use to make the formula alkaline. The new formula was sold by the Platinotype Company in London as Sulpho-Pyrogallol Developer.[10]
Nineteenth-century experimentation with photographic processes frequently became proprietary. The German-born, New Orleans photographer Theodore Lilienthal successfully sought legal redress in an 1881 infringement case involving his "Lambert Process" in the Eastern District of Louisiana.
A camera obscura box used for drawing images
Photography is the result of combining several technical discoveries. Long before the first photographs were made, Chinese philosopher Mo Ti and Greek philosophers such as Aristotle and Euclid described a pinhole camera in the 5th and 4th centuries B.C.E,[2][3] Ibn al-Haytham (Alhazen) (965–1040) studied the camera obscura and pinhole camera,[3][4] Albertus Magnus (1193/1206-1280) discovered silver nitrate, and Georges Fabricius (1516-1571) discovered silver chloride. Daniel Barbaro described a diaphragm in 1568. Wilhelm Homberg described how light darkened some chemicals (photochemical effect) in 1694. The novel Giphantie (by the French Tiphaigne de la Roche, 1729-1774) described what can be interpreted as photography.
For years images have been projected onto surfaces. According to the Hockney–Falco thesis as argued by artist David Hockney,[5] some artists used the camera obscura and camera lucida to trace scenes as early as the 16th century. However, this theory is heavily disputed by today's contemporary realist artists who are able to create high levels of realism without optical aids.[6] These early cameras did not record an image, but only projected images from an opening in the wall of a darkened room onto a surface, turning the room into a large pinhole camera. The phrase camera obscura literally means dark chamber. While this early prototype of today's modern camera may have had modest usage in its time, it was an important step in the evolution of the invention.
Development of chemical photography
The first permanent photograph was an image produced in 1825 by the French inventor Joseph Nicéphore Niépce. His photographs were produced on a polished pewter plate covered with a petroleum derivative called bitumen of Judea. Bitumen hardens with exposure to light. The unhardened material may then be washed away and the metal plate polished, rendering a negative image which then may be coated with ink and impressed upon paper, producing a print. Niépce then began experimenting with silver compounds based on a Johann Heinrich Schultz discovery in 1724 that a silver and chalk mixture darkens when exposed to light.
In partnership, Niépce (in Chalon-sur-Saône) and Louis Daguerre (in Paris) refined the existing silver process.[7] In 1833 Niépce died of a stroke, leaving his notes to Daguerre. While he had no scientific background, Daguerre made two pivotal contributions to the process. He discovered that exposing the silver first to iodine vapour before exposure to light, and then to mercury fumes after the photograph was taken, could form a latent image. Bathing the plate in a salt bath then fixes the image. On January 7, 1839 Daguerre announced that he had invented a process using silver on a copper plate called the daguerreotype.[8] The French government bought the patent and immediately made it public domain.
In 1832, French-Brazilian painter and inventor Hercules Florence had already created a very similar process, naming it Photographie.
After reading about Daguerre's invention, Fox Talbot worked on perfecting his own process; in 1839 he got a key improvement, an effective fixer, from John Herschel, the astronomer, who had previously showed that hyposulfite of soda (also known as hypo, or now sodium thiosulfate) would dissolve silver salts. Later that year, Herschel made the first glass negative.
By 1840, Talbot had invented the calotype process. He coated paper sheets with silver chloride to create an intermediate negative image. Unlike a daguerreotype, a calotype negative could be used to reproduce positive prints, like most chemical films do today. Talbot patented[9] this process, which greatly limited its adoption. He spent the rest of his life in lawsuits defending the patent until he gave up on photography. Later George Eastman refined Talbot's process, which is the basic technology used by chemical film cameras today. Hippolyte Bayard had also developed a method of photography but delayed announcing it, and so was not recognized as its inventor.
In 1851 Frederick Scott Archer invented the collodion process.[citation needed] Photographer and children's author Lewis Carroll used this process.[citation needed]
Slovene Janez Puhar invented the technical procedure for making photographs on glass in 1841.[citation needed] The invention was recognized on July 17, 1852 in Paris by the Académie Nationale Agricole, Manufacturière et Commerciale.
Roger Fenton's assistant seated on Fenton's photographic van, Crimea, 1855.
Herbert Bowyer Berkeley experimented with his own version of collodian emulsions after Samman introduced the idea of adding dithionite to the pyrogallol developer.[citation needed] Berkeley discovered that with his own addition of sulfite, to absorb the sulfur dioxide given off by the chemical dithionite in the developer, that dithionite was not required in the developing process. In 1881 he published his discovery. Berkeley's formula contained pyrogallol, sulfite and citric acid. Ammonia was added just before use to make the formula alkaline. The new formula was sold by the Platinotype Company in London as Sulpho-Pyrogallol Developer.[10]
Nineteenth-century experimentation with photographic processes frequently became proprietary. The German-born, New Orleans photographer Theodore Lilienthal successfully sought legal redress in an 1881 infringement case involving his "Lambert Process" in the Eastern District of Louisiana.
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About Me
- Roshan
- I believe that JESUS CHRIST is the son of GOD and that he is has saved me from my sins. Iam pressing on to be a better Christian everyday. Iam imperfect but he is perfect and so he is the only one to be worshipped and adored. I believe that he came into this world to be a perfect sacrifice for mankind, so that anybody who believes with all their heart that "Jesus died for me" will be saved.