Digital photography or digital imaging touches nearly every industry in some way. Without it our lives would surely be very different. In my this and future blog postings, I will be discussing the history of photography and the advent of digital photography. Particularly, how it has affected business and what the future holds.
Since the first photograph was taken in the early 1800’s in France, thousands upon thousands of people have taken photographs of some sort. According to ZDNet, fifty billion digital photos were taken in 2007. That’s a lot of photos.
The first photograph, taken in 1826 in France by Joseph Nicéphore Niépce, had an eight hour exposure. By today’s standards, that’s unheard of. It was a very grainy picture of the landscape from a window in his home using a technique he called “heliography”. But it wasn’t until 1939 that the term “photography” was coined by Sir John Frederick William Herschel. It was in that same year that the that Robert Cornelius took the very first human portrait.
The first commercially viable process developed by French chemist Louis Daguerre was called “daguerreotype”. This was an expensive process and required special equipment but was used widely by professionals in France and the US.
In 1888, George Eastman invented Celluloid Film which is still in use today, although it is quickly being replaced with the advent of digital photography.
NASA began using digital signals in the 1960’s to get pictures of the moon sent back to earth from space probes. This technology was instrumental in the development of today’s digital camera technology. George Smith and Willard Boyle are credited with developing the charge-coupled device (CCD) that has been used in most of today’s digital cameras.
Photos from the early CCD were not very usable as the resolution was very low. Finally in 1986, Kodak developed the first megapixel CCD. Since then, the megapixel hype has dominated the digital market. Manufactures have worked feverishly to increase the resolution of their devices. Today, the average consumer can purchase 12 megapixel point-and-shoot digital cameras for under $200. Photos at this resolution can be printed with very high quality at 20x30 inches or more. When was the last time the average camera user printed anything that large?
The charge-coupled device that is the heart of most of today’s digital cameras works because it has millions of small light receptors called “photosites”. Each of these photosites represents one of the primary colors for one pixel. When the photographer presses the camera’s button, light is allowed to enter the lens and is focused on the CCD sensor. The amount of light that hits each of the photosites is registered as a number that represents the intensity of the light at that point. This array of numbers is then stored in memory. When one views one of these photos on a computer, the numbers are converted back into colored dots (pixels) and displayed on a screen.
Most cameras have software built in that processes the images before they are actually stored in memory. The software in most cameras convert the image from its raw format right from the sensor to the common jpg format for storage. It is often during this conversion process that the built-in software makes adjustments to the image based on camera settings such as exposure and type of lighting. Most manufacturers add other tasks to this conversion process to clean up the image from sensor noise and other inherent image problems caused by the imperfect technology. Thanks to the programming efforts by the manufacturer, we see nice clean and sometimes corrected images.
Some of the higher end digital cameras will allow the photographer to save the original “raw” image just as it comes from the sensor. This image format is ingeniously called “RAW” format. Before it can be viewed by traditional software, it must be converted to one of the more common image formats such as jpg, bmp, or gif. The advantage with the raw format is that photographers have more power to manipulate the image they way they want instead of having to live with what the manufacturer decided was best. From this format, photographers can manipulate the photos in ways that cannot be done once the image is in one of the traditional formats.
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