Did you know that early cameras were created for the purpose of studying optics instead of taking pictures? The art of photography has hardly been around for two centuries, but in that short time it has seen no small number of evolutions in technique, from large cameras to developing film and finally to a condensed imaging device through which we can instantly snap and share images. Today, nearly everyone has access to a camera and taking pictures can be an everyday affair for many of us. How has such a useful tool been developed over the decades?
The First Camera
Writings dating back to as early as 400 BC have been found mentioning a device called the camera obscura. These were penned by Chinese scholars, and also some decades later by Aristotle in circa 330 BC. However, it was not until the Arab scholar Ibn Al-Haytham (945-1040) that the very first contraption that functioned similar to a camera was created. Ibn Al-Haytham, also known as Alhazen, was the first person to study how sight worked. His invention was called the camera obscura and it was used to project an image onto a flat surface with the use of light.
The camera obscura would remain as it was for the next few centuries until the mid-1600s. When finely crafted lenses were invented, artists would use the camera obscura to visualize real world images and scenes which they would then use as a reference for drawing and painting.
Another invention surfaced around this time, called the “magic lantern”. It made use of the same optical principles as the camera obscura and acted like a projector. People would paint images on glass sides and project them onto surfaces such as walls with a magic lantern. These would be used as a tool for entertainment.
In 1727, the German scientist Johann Heinrich Schulze conducted some experiments with photo-sensitive chemicals, discovering that silver salts were sensitive to light. He did not explore this discovery more at the time, but these findings would be used in the next century to produce permanent images on a surface – the world’s first photographs.
The First Photograph
In 1827 – a hundred years after Schulze’s experiments – the French scientist Joseph Nicephore Niepce developed the world’s first photograph. The image had been captured with a camera obscura in 1826 and was of the view outside Niepce’s window in France. He created a permanent image by placing an engraving onto a metal plate coated with bitumen. When it was exposed to sunlight, the light was able to penetrate the whiter parts of the engraving, reacting with the chemicals on the metal plate. Niepce placed the plate in a solvent, noticing that an image was gradually forming, although it faded away shortly. While considered by many to be the first photographic images, this rudimentary technique was less than ideal as it did not produce a lasting image while requiring long hours of light exposure to produce the image.
Two years later in 1829, Niepce started working with another French scientist, Louis Daguerre, who had also been trying to develop images from a camera. It would take them a decade and Niepce’s death before Daguerre eventually developed a method of photography that was more effective and convenient than before.
The daguerreotype thus came about. It used a process in which images were fixed onto a silver-plated copper sheet. The surface would then be polished and covered with iodine, which made it sensitive to light. When this sheet was placed in a camera and exposed to light for some minutes, an image would form on it, after which the sheet would be immersed in a silver chloride solution. This was a much more effective way of developing a picture that was both much quicker – it only required a few minutes of exposure time – and long-lasting, as the image would not fade away even if exposed to light.
This technique was popularized by Daguerre and Niepce’s son. It quickly caught on in popularity across Europe and the United States, with New York City reportedly having over 70 daguerreotype studios by 1850.
Multiple Prints with the Calotype
While the daguerreotype made it possible to capture real-world images, it had one major drawback – each image produced was unique and could not be duplicated. It was the Englishman Henry Fox Talbot who came up with the possibility of creating multiple prints in the 1840s. As Schulze had discovered more than a century earlier, silver salts were sensitive to light. Talbot used a silver-salt solution on paper which he then exposed to light, creating a negative image, where the background was black and the details of the image were in greyscale or white. He made contact prints by using the negative image as a template and reversing the light and shadows, a process which he called calotype – which translates to “beautiful picture” in Greek.
Following the daguerreotype and calotype, other scientists and photographers began to experiment and innovate on these ideas. By the middle of the 19th century, there were a number of variations on photography techniques that were improvements on their predecessors.
Wet-plate Negative (Collodion Process)
In 1851, the English sculptor Frederick Scoff Archer and the French photographer Gustave Le Gray did their own improvements on Talbot’s calotype, coming up with the collodion process at almost the same time. The collodion process used a viscous solution of collodion – a flammable alcohol-based substance – to coat glass with silver salts. This would create a more stable and detailed negative, called the wet-plate negative, since the material of the negative image was glass instead of paper.
Since it was wet, the negative image had to be coated, sensitized, exposed and developed within approximately 15 minutes before the emulsion dried. This was rather impractical for those capturing images of the outside world, as one would have to carry around a portable darkroom containing all the toxic chemicals required for the developing process.
A dry form of collodion was also available, but at the cost of significantly increased exposure time. As such, most photographers doing portraiture work often kept to using the wet form of collodion, while dry collodion was usually only used for landscape photography.
The tintype was patented in 1856 by Hamilton Smith in the United States and by William Kloen in the United Kingdom. Its process was similar to the daguerreotype in making use of thin metal plates covered in a light-sensitive substance. However, the tintype used iron instead of copper, which would yield a positive image.
Tintypes grew in popularity compared to daguerreotypes since they were very inexpensive and also easy and quick to make. A tintype image could be ready just a few minutes after the picture was taken. Tintypes were most commonly made in booths at fairs and carnivals since they were convenient, resilient and did not require any drying.
The dry plate was invented by Dr. Richard Maddox in 1871, solving the problem of wet plating methods. The dry plate technique used a glass plate to capture an image, but the difference was that the plates could be coated with a dried gelatin emulsion, allowing them to be stored for some time. As such, photographers no longer had to carry a darkroom around with them and could develop the images as and when it was convenient. This also resulted in some photographers hiring technicians to develop the images for them.
The first photographic film was created by George Eastman in 1885, made of a flexible roll of paper. Its material was later changed to a transparent plastic nitrocellulose in 1889.
With the invention of the film, it was possible to create a mass-produced box camera by coating emulsions on a cellulose nitrate film base. These images were mostly six centimeters wide and were either rectangular or square.
In 1913, Kodak invented a 35mm film for motion picture technology, which other companies caught on to. The German camera maker Leica was the first to use a 35mm film on a still camera. With the invention of refined film formats, photographers no longer used glass plates and instead switched to the more sturdy and flexible film rolls.
However, nitrocellulose film was highly flammable and dangerous. Kodak soon introduced the safety film, which was made of cellulose acetate and intended to be a replacement for nitrocellulose. However, nitrocellulose film was still tougher, more transparent and cheaper than safety film, so the safety film did not completely take over until more types of film were improved, such as triacetate, which was more stable, flexible and not volatile. Up till the 1970s, most images were produced using triacetate film.
The first photograph prints were made on linen rag papers. The prints were coated with a gelatin emulsion to make them stable, and the papers were usually toned with sepia or selenium to enhance their stability. However, the paper could still dry out and crack over time if poorly stored. Additionally, prints were susceptible to leftover chemical residue from image processing. The prints could also be damaged if there were contaminants left in the water used for processing and washing, or if the print was not properly washed, which would often result in discoloration of the image.
Photographs were then printed using resin coating or water resistant paper. To achieve this, normal fiber paper would be coated with a polyethylene substance. The emulsion would then be placed on a paper base with plastic covering. However, this meant the image stayed on the plastic coating and as such could fade over time.
Up till the 1940s, photography was all done in greyscale. The first commercially viable color films were introduced by Kodak and Agfa, among other film companies, making use of chemical dye-coupling to connect three dye layers in the film and create a color image.
The first prints of color images were done using organic dyes, but these were highly unstable and did not last. The images would vanish from the print base as the dyes deteriorated. The first improved version of color printing, invented by Kodak and named Kodachrome, was able to last for up to half a century. It was created by a development team headed by two classical musicians, Leopold Mannes (“Man”) and Leopold Godowsky Jr. (“God”). Kodachrome’s color printing was done by layering three parts of emulsion on a single base, corresponding to red, green and blue respectively. The color film would be loaded into the camera and the picture taken the normal way, and then the camera would be sent to Kodak with the film inside for processing.
The actual process of developing the color image was much more complicated. Each layer was developed into a greyscale silver image with the addition of a chemical dye coupler, which would cause an image in cyan, magenta or yellow to be created along with the silver default. The silver images would then be chemically removed, retaining only the three layers of dyed images and creating a color image.
Color printing was then improved to last for two centuries, and now the modern times have brought highly stable and permanent color pigments.
The very first instant camera was called the Land Camera 95, invented by the American inventor and physicist Edwin Herbert Land in 1948. At the time, Land was already looking into inventing polarized lenses by utilizing light-sensitive polymers. This instant camera would become the Polaroid, incorporating film into fast and cheap cameras that could develop photographs in an instant. Polaroid cameras started to develop in color in 1963. This first instant color camera used a negative-positive process, peeling the negative part away from the film to produce a unique photograph. The negative part, still full of chemicals, would be discarded as it could not be reused. However, this caused large amounts of littering especially at popular sites for photographs. Land then created the Polaroid SX-70, which did not produce any discarded part.
Polaroid was not the only company that ventured into instant photography, either – other photography firms such as Kodak and Fuji also created their own versions of instant cameras soon after.
The first semblance of digital photography began with the invention of the charged couple device in 1969. Created by Bell Labs, the device would convert light to an electronic signal, thus creating a digital image. In 1975, the first digital camera was created, using a cassette recorder to store data. However, it was extremely inefficient, taking more than 20 seconds to capture a photo.
In 1976, Bryce Bayer invented the Bayer filter, in which a light-sensitive sensor is placed behind a color filter. Each pixel has its own light response curve, usually responding to red, green and blue. Since it is believed that the human eye is more sensitive to variations in green than the other colors, the response of green is used twice as often as red or blue. This allows the replication of a color image as realistic as possible to what people see.
The Bayer filter is used most often in digital photography, but there are also other methods. The Foveon sensor uses a stack of silicon to compute the intensity of the light as well as its color since light penetrates silicon to a depth according to its exact wavelength, which produces the color. The sensor reads light at multiple layers in the stack to determine how far it penetrates and thus deduce its color.
Over the years, modifications to these methods were proposed and other film companies similarly created their own digital cameras, making digital photography the dominant form of photography. Today, many smartphones, hobbyist cameras and professional photography rigs rely on digital photography to capture clear images.