Wednesday, May 5, 2010

Digital Photography

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     Digital Photography is a form of photography in which images are encoded digitally as sequences of 0s and 1s. These images can come from a variety of sources including digital cameras and scanners. Introduced in the 1950s, Digital Photography has come a long way. Originally inferior to traditional Analog Photography, Digital Photography has now surpassed it in most comparisons.
As evidence, most professional photographers such as Moose Peterson have switched over to Digital Photography (“Occupational”). The drastic changes brought by Digital Photography have also transformed the way that photography itself is practiced. Even advertising has been affected. Furthermore, the ease of photograph manipulation through digital techniques has led to many consequences. Through all of this, Digital Photography has persevered: Digital Photography is practiced in all parts of the world by all kinds of people.
     All digital photographs are stored digitally as linear sequences of 0s and 1s, which represent grids of square pixels that vary in color. These pixels can be extremely small. For example, an average 15 inch laptop screen contains almost one million unique pixels (Chastain)! Viewed from a distance, the human mind perceives these grids of pixels as images. The most basic digital image format is binary bitmap, in which each pixel can represent either black or white. Figure 1 depicts a stick figure of resolution 35x48 (1,680 pixels) and a zoomed in view of the same image. As is evident, our brains perceive this set of 1,680 pixels as a stick figure. A more advanced digital image format is true-color bitmap, in which each pixel represents one of over sixteen million different colors. Today, most digital images use formats that support color (King 26). Digital photographs also vary greatly in resolution, the number of pixels they contain. For example, the stick man in figure 1 has a resolution of about two thousand pixels, while most digital cameras today can capture photographs with over one million pixels each (King 29-30).
    Digital photographs can be stored in a variety of different digital file formats such as BMP, JPEG, GIF, and PNG. All of these formats are represented as a linear sequence of 0s and 1s. Currently JPEG is the most common format used for photographs due the low file sizes it produces through advanced image compression methods (King 53-54). However, the most basic photograph format is binary BMP, in which each black pixel is represented as a 0 and each white pixel is represented as a 1 (or vice versa). Stored in a linear sequence, these 0s and 1s are later interpreted as image files based on header data located at the start of the BMP file. For example, a sequence 101010 in a binary BMP file can be interpreted as an image with a width of 2 pixels and a height of 3 pixels containing (from left to right and top to bottom) a white, black, white, black, white, and black pixel (see fig. 2). Of course, this image is incredibly small in resolution, but binary bitmap images of any resolution can be represented in this way (Chastain).
    Born in the 1950s, Digital Photography is a relatively new form of photography. “What would happen if computers could look at pictures?” Working at the National Bureau of Standards, Russell Kirsch and his colleagues asked this question (Baum). By 1957, they had developed the drum scanner, a device able to scan photographs into a digital format readable by computers. Testing their device, Kirsch and his colleagues scanned one of the first digital photographs in history: an image of Kirsch's infant son (see fig. 3) (Baum).
    However, it was not until 1975 that the digital camera was invented. Working with spare analog camera parts and computer chips, Steven Sasson, a researcher at Kodak pieced together the first digital camera (Sasson). Unlike traditional cameras, the digital camera required no film: it directly captured digital photographs. And, unlike scanners, the digital camera was portable. However, Kodak kept Sasson's invention from the public until 2001—perhaps because the photography company was heavily invested in film at the time (Sasson). As a result, it was not until 1981 that the first digital camera was made available to the public. Designed independently by Akio Morita, the Sony Mavica shocked the world (Clancy). Although inferior to most film cameras of the time, the Sony Mavica signaled the beginning of the age of digital cameras.
    When Digital Photography was first introduced, it had many disadvantages over traditional, film-based Analog Photography. However, most of these disadvantages have been eliminated over the past fifty years (King 13).
    Until recently, analog cameras have held one main advantage over digital ones: quality (King 20-21). Today, digital cameras have surpassed film cameras in quality. As a rough comparison, an 8-megapixel digital camera (available for under $100) produces images about equal in quality to those produced by a standard film camera (King 13). However, the only area where Analog Photography arguably still surpasses Digital Photography is tonal range, the range of brightness levels that can be represented in an image. This is partly due to the fact that the most common digital photograph formats support only 256 different brightness levels. On the other hand, film supports a theoretically unlimited number of levels (Bunks). The detrimental effects of limited tonal range can be seen in digital photographs of clouds: certain areas are “burned out” because there are not enough brightness levels to represent all the different shades of the cloud (see fig. 4). However, this problem is being worked out. High Dynamic Range cameras, digital cameras with larger tonal ranges, are currently being developed and sold. Support for larger tonal ranges has also been added to many digital image formats (Bunks). Another disadvantage of digital cameras is that they have a relatively large “lag time.” That is, a digital camera requires a short time period before it can capture another photograph. The cause of this delay is the time needed to encode an image file into computer memory. However, this problem is also being worked out. Many inexpensive digital cameras available today offer lag time comparable to that of film cameras (King 20-21).
    On the other hand, Digital Photography has many obvious advantages over Analog Photography. The most important of these advantages is simply that digital photographs are computer files. This imminent property of digital photographs leads to many benefits. First, thousands of high quality digital photographs can be stored on a computer chip the size of a dime. Second, digital photographs can be transmitted across the world through the use of the Internet. Third, digital photographs are relatively permanent as they can be duplicated instantly and are not subject to quality loss over time. Fourth, digital photographs are much easier to edit than are analog photographs as a plethora of powerful computer-based photograph editing programs are available. Fifth, digital photographs are much cheaper to produce than are film-based photographs. Sixth, digital cameras allow photographers to immediately see the photographs they took (King 13-19). Although easily overlooked, traditional photography has also had a very negative impact on the environment, as it required the production of many exotic chemicals, huge amounts of water (to wash photograph negatives and positives), and large amounts of ink and paper (through the necessity for prints). Digital Photography, on the other hand, is very environmentally friendly, as digital cameras consume only electricity and photographs need not be printed to be seen (Kerr). Overall, Digital Photography is a more practical choice than Analog Photography. This is signaled by the fact that most professional photographers today deal solely with Digital Photography (“Occupational”).
    Digital Photography has made a large impact on the use of photography. Because of the low cost of digital cameras and camera cell phones, the number of photographers has risen to unprecedented levels. And due to the relative ease with which digital photographs can be taken, most photographers now take more photographs: “I might take 20 pictures of birds at my bird feeder to get one or two to share. With film, I would have stopped at four” (Wallack). Combined, these two changes have caused the production of an unimaginable number of photographs. Today, most photographs are never printed or even viewed again after they are taken (Wallack). Bad shots are instantly deleted. Photographs of all kinds have become widely and freely available through the Internet. Yet professional photography continues to grow. In fact, the demand for professional photographers grows about 10% annually in the United States (“Occupational”).
    The changes in the practice of photograph manipulation brought by Digital Photography have also led to many consequences. Although photograph manipulation was practiced as early as 1860, it was usually a professional endeavor due to the large amount of work required (Wallack). Today, photograph editing has become extremely simple, powerful, and instant through the use of computer programs (King 13). Increasingly widespread, photograph manipulation has been used for many purposes. A user posting images to a dating site may crop out a girlfriend or boyfriend from an earlier photograph. A fashion photographer may digitally remove blemishes from a model's face. A newspaper photographer may digitally transform a color photograph into a black-and-white one (Wallack). On the other hand, the nature of digital photograph manipulation has provided much room for doubt in the validity of photographs. Today, it is impossible to tell a well-doctored photograph from an unedited one. This has caused many problems. Digitally-manipulated photographs of models depicting unachievable levels of beauty have led to many self-image problems such as depression and anorexia around the world (Williams). Manipulated photographs of political candidates have angered many. Photographs modified to be “socially acceptable” have outraged others. One recent example of this is the Microsoft race-swap incident in August 2009. On Microsoft's United States website, a photograph of three businessmen was coupled with text promoting Microsoft. Concurrently, an edited version of the same photograph was displayed on Microsoft's Polish website (see fig. 5). In the photograph on the Polish website, an African American businessman in the center of the original photograph had been replaced with a White businessman. Soon after realizing their mistake, Microsoft issued an official apology: “We apologize and are in the process of pulling down the image” (Fried). As can be seen from this incident, Digital Photography has made “the photograph never lies” an increasingly gullible statement.
    Used by politicians and companies to promote themselves (or defame opponents), advertisements have been greatly affected by Digital Photography. Historically, persuasive photographs were fed to the public through relatively static mediums such as magazines, newspapers, and fliers. The advent of Digital Photography made possible the use of wide-reaching, dynamic mediums for advertising. The most commonly used of these mediums is perhaps the Internet, where digital banner advertisements displayed on websites make use of digital photographs to attract hundreds of millions of customers. However, the fact that less than 1% of banner advertisements displayed are ever clicked on, has shifted the style of Internet advertising (Hochman). Many advertisers now aim not to immediately gain customers, but instead to modify implicitly held beliefs to attract future business (Hochman). This is partially accomplished through the use of heavy photograph manipulation.
    One of the most famous digital photographers today is Moose Peterson. Encountering the new form of photography in 1999, Peterson was one of the first wildlife photographers to switch to Digital Photography. Making use of the flexibility of Digital Photography, Peterson has captured more than 850 species of animals on camera (“Moose”). Peterson has also offered valuable insight into why he prefers Digital Photography: “There is no greater fun than shooting digital. […] Digital is unique because it gives us the ability to improve our photography. We can see what we did right, what we did wrong, which story elements we captured and which ones we need to still to get” (Peterson).
    Much like photography transformed painting, Digital Photography has transformed photography. Today, everyone is free to pursue photography and to share their work with others around the world.

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