The History of Photography
The art of replicating and copying real life has been around for thousands of years, but scientists first started experimenting with photographic techniques in the 9th century.
10th Century
Alhazen was an astronomer, mathematician and scientist born in 965 who developed the first Camera Obscura, a large, dark room with a small hole through which light could filter in one wall, which couldn't capture an image but helped artists and painters draw an outside scene. He worked out that the optic law was the reason the image appeared upside down on the flat surface. Famous Rennaissance artists such as Leonardo Da Vinci used a Camera Obscura to achieve accurate perspective.
1724
Johann Heinrich Schulze discovered that by dissolving some silver into a mixture of chalk and nitric acid, an image could be produced when it came into contact with sunlight, but not heat. He tested this by applying stencils of words to the outside of a bottle filled with the silver compound, and it left dark letters on the surface of the bottle. However the letters were temporary and would disappear when they were exposed to light for too long or if the bottle was shaken.
1839
Louis Daguerre was a French inventor and photographer, and studied light-sensitive silver salts. He exposed a thin silver-plated copper sheet to the vapour given off by iodine crystals, producing a light-sensitive coating on the surface. This was then exposed in the camera. The process, called the daguerrotype, took a very long time which meant that capturing any images other than still life was virtually impossible. Later on, discovered that a very faint "latent" image made by a much shorter exposure time could be "developed" into a visible image using vapour given off by heating mercury to 75 °C. This gave a visible image which was made insensitive to any more exposure to light by taking out the unaffected silver iodide using saline water.
In England, Henry Fox Talbot was experimenting with "salted paper", which was writing paper dipped in a solution of sodium chloride and then brushed on one side with silver nitrate, which was light-sensitive. These could be used for "photogenic drawings" and creating shadow images. Shortly after the release of the daguerrotype, Henry Fox Talbot started working on his calotype, a developing process. The calotype negative made it possible to produce as many positive prints as you wanted by simple contact printing, and it was much quicker than previous methods, taking only a few minutes of exposure in sunlight. He released the calotype in 1841.
1879
George Eastman invented the dry plate process. He developed a machine to coat plates and opened the Eastman Film and Dry Plate Company, reducing the cost of photography and making it more available to the public. He invented the first Kodak camera, which was the most widely used camera for over 30 years. In 1900, Kodak released the Brownie camera, targeted at children because of its $1 price tag. It was also used by servicemen. Eastman supported the war effort too by developing unbreakable glass lenses for gas masks and a special camera for taking pictures from planes during World War I.
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Well done, plenty of extra research completed and careful presentation. EBI- include more images created by the separate processes.
Camera Obscura
The Camera Obscura was one of the first attempts at capturing reality without using solely the human eye. To make our camera obscura, first we took a cardboard box and cut a small square hole in the centre of one side. We cut out most of the opposite side, leaving a small border so we could tape on a piece of tracing paper, which would become our canvas, and which the light would be reflected on to so we could draw the scene we were seeing.
To focus on a subject, we used a magnifying glass as a lens to make the image clearer. To make it more in focus we had to change the focal length, which is the distance of the lens from the camera. The image we were seeing with our eyes was projected on to the back of our camera obscura and we could draw it. The image appears flipped vertically because of the optic law Alhazen discovered in the 10th century, where the light from low areas comes through the hole in the camera at the top, and light from high areas comes in through the bottom of the hole. The camera works best when it is in a dark area, looking out to a well lit area because the light is more concentrated. We weren't able to do this very well in our surroundings, because everywhere had fairly high light levels, which is why the image looks blurry and unclear.
To focus on a subject, we used a magnifying glass as a lens to make the image clearer. To make it more in focus we had to change the focal length, which is the distance of the lens from the camera. The image we were seeing with our eyes was projected on to the back of our camera obscura and we could draw it. The image appears flipped vertically because of the optic law Alhazen discovered in the 10th century, where the light from low areas comes through the hole in the camera at the top, and light from high areas comes in through the bottom of the hole. The camera works best when it is in a dark area, looking out to a well lit area because the light is more concentrated. We weren't able to do this very well in our surroundings, because everywhere had fairly high light levels, which is why the image looks blurry and unclear.
Well done, a comprehensive presentation of the process. I like the link back to Alhazen.
Shutter Speed
Shutter speed is how long the camera's shutter is open to let light in and how long the sensor is exposed to light. It is measured in fractions of a second if the exposure time is under one second.
Phillipe Halsman
Philippe Halsman was born on 2 May 1906 in Latvia, and was an American photographer. He mainly took portraits of people and shot many well known celebrities in the 20th century, such as Marilyn Monroe, Winston Churchill and Pablo Picasso. His 'Jump' series showcased famous people jumping in the air, which Halsman believed enabled them to express their true selves through the faces they made. In his Jump Book released in 1959, a compilation of all the photos he took in the 1950s of people jumping, Philippe Halsman wrote "I was motivated by a genuine curiosity. After all, life has taught us to control and disguise our facial expressions, but it has not taught us to control our jumps. I wanted to see famous people reveal in a jump their ambition or their lack of it, their self-importance or their insecurity, and many other traits."
I particularly like this photo of American actress Dorothy Dandridge jumping, as it shows her looking carefree and expressive in mid-air, while still appearing beautiful and regal. Philippe Halsman showed through this series of photos what people, particularly celebrities under pressure to come across well to the public, may often have kept hidden. I like this because it makes the photos seem personal, and gives them more depth and meaning. Another thing I think is clever about this photo is how all of her is in focus apart from her hands, allowing us to get a sense of movement as well as a person suspended in time. |
My Jumping Photos
Inspired by Philippe Halsman and his jumping series, I took 3 photos of a friend jumping to show how an image changes depending on the shutter speed.
The first image, taken with a shutter speed of 1/30th of a second, is blurry because the shutter was open long enough to capture lots of movement, including a bit of camera shake. The second photo, 1/100th of a second, is mostly still, however her feet and hands are blurred. In the last photo, 1/500th of a second, she appears suspended in mid-air. This shows that a by using a faster shutter speed we can make a moving object seem still.
The first image, taken with a shutter speed of 1/30th of a second, is blurry because the shutter was open long enough to capture lots of movement, including a bit of camera shake. The second photo, 1/100th of a second, is mostly still, however her feet and hands are blurred. In the last photo, 1/500th of a second, she appears suspended in mid-air. This shows that a by using a faster shutter speed we can make a moving object seem still.
Aperture
Aperture is the size of the hole which allows light into your camera. The higher the number, the smaller the hole, giving you a wider depth of field which means more of the image will be in focus. A small number gives you a shallow depth of field so only the people or objects in the foreground will be in focus.
In the first image, the aperture is low so only Daphne is in focus. In the second image with a medium aperture, you can see Sophie becoming more in focus but Ella is still blurry. In the last image, the aperture is high and all three of them are in focus. WWW: I used aperture to get effective photos. EBI: I could have included slightly less background to make the subjects look more focused.. |