A digital camera is an electronic device that records and stores images and videos digitally as pixels, rather than on film. Texas Instruments patented the first filmless electronic camera in 1972. In 1975, Steven Sasson, an engineer working for Kodak, built the first digital camera using a charge-coupled device (CCD) to replace film. The resulting images were recorded onto a tape cassette. Digital photography started as a technical niche market, and many companies and professionals alike felt it would never replace film. Kodak, then the world's largest manufacturer of film, ignored its own digital invention and the steady rise of digital photography until it was too late to recover. Kodak filed for bankruptcy in 2012. In 2015 alone, more than one trillion digital photos were taken worldwide. The number is expected to grow to 1.3 trillion by 2017. Of this staggeringly large number of photos taken, 75 percent are now taken with mobile phones. The percent of stand-alone digital cameras used around the world is expected to drop to just 13 percent by 2017 as more and more people use mobile phones as their camera of choice.
A digital single lens reflex camera (DSLR) incorporates a mirror and a prism system behind the lens so that the photographer can see the exact image that will be recorded digitally. Interchangeable lenses are used with this type of camera. An optical viewfinder is used to see through the lens before the picture is taken. The mirror behind the lens shifts out of the way just as the photo is taken. This type of camera is most similar to traditional single lens reflex (SLR) film cameras and uses a charge-coupled device (CCD), or complementary metal-oxide semiconductor (CMOS) sensors, in place of film. The larger sensors found in DSLR cameras result in images with a high resolution, or more detail. DSLR cameras also produce greater bit depth for images, which is the variation of colours a single pixel can display. Higher resolution and greater bit depth produce more detailed images with a greater overall range of colours displayed. A liquid crystal display (LCD) screen on the back of DSLR cameras allows the photographer to see the digital image both before and after it has been reordered. DSLR cameras are used by professionals and semi-professionals and have very large image sensors that yield the highest quality digital images.
Point-and-shoot digital cameras are small or compact cameras designed for automatic ease of use. Within this category there are cameras with optical and digital zoom lens capabilities. The combination of small size and automatic features along with high image quality make point-and-shoot cameras a good choice for untrained photographers. Current point-and-shoot cameras are often advertised as having the capabilities of producing images superior to mobile phone cameras. Despite their advantages over mobile phone cameras, the point-and-shoot market has continued to shrink as the quality of mobile phone cameras has improved.
Digital camera parts can vary wildly among cameras, but most share many common parts. Some digital cameras have parts so small they may be unrecognizable to the user. On a large DSLR camera, parts such as the body and lens are obviously similar to traditional cameras. On a mobile phone, however, the lens is often incredibly small and can easily be covered with a person's finger. When mobile phones first came equipped with cameras, they were low-quality novelty features. Today the quality on many mobile phones is so good that the mobile phone market dominates the source of photos taken around the world. Images taken with an iPhone can easily be used professionally and have even been seen on massive billboards to advertise image quality.
Digital images taken with all digital cameras must be stored on physical media that will enable the image to be played back and manipulated. Storage media for most digital cameras are tiny reusable memory cards that come in various storage sizes. As the quality of digital images has improved over the years, so too has the amount of storage available on memory cards. The size of memory cards, too, has gotten smaller and smaller as technology has improved. Micro SD memory cards are now available for portable digital devices that are smaller than a postage stamp and can hold 128GB (gigabytes) of images. One GB of storage capacity is equivalent to one billion bytes of information.
Software provides the digital commands or instructions a camera uses to control various aspects of digital photography. Software that is permanently installed onto a digital camera or other digital device is called firmware. Each type of digital camera has unique software programmed into it. Firmware can sometimes be updated by connecting the digital camera to the Internet and downloading updated firmware made available by the manufacturer of the digital camera or device. Updated firmware for digital cameras typically adds new and improved features. For example, software updates might eliminate system-wide programming errors, called bugs, or they might improve battery life, exposure, and other camera features.
Many of the basic processes and principles found in traditional photography are present in digital photography. Light still enters a digital camera and the resulting image seen by the photographer must be composed and then the shutter clicked. Camera manufacturers have gone out of their way to make taking digital pictures as simple as possible, incorporating software and hardware that aid in light metering, colour balance, and focusing so that the photographer is met with as much success as possible capturing the image.
Computers are an integral part of modern digital photography. With film photography, film rolls needed to be developed and then the resulting negatives needed to be printed onto light-sensitive paper in darkrooms. Chemicals and specialized equipment were required for processing, and the consumer photographer brought rolls of film to a store for development and printing. With digital photography, computers and various types of software replace the traditional darkroom and anyone—pro or amateur—can crop, colour-correct, lighten, darken, and manipulate digital photos with software such as Adobe Photoshop, Lightroom, or various photo applications, called apps. Computers with many gigabytes or terabytes of internal or external storage can hold thousands of digital images that can be printed from home ink jet and laser printers, or uploaded to companies through the Internet for the creation of books, cards, and even posters made from the images people take. Even mobile phones have the ability, with various software apps, to adjust and alter digital photos and print them wirelessly via Wi-Fi.
The next most common image file format that cameras use is the Camera RAW format. Raw images are uncompressed and take up much more space than a JPEG image of the same size. Images in the Camera RAW format contain all the information that the camera's sensor recorded. RAW files need to be converted with a RAW converter to be viewed on a device or a computer. Professional photographers often take photos using the Camera RAW file format because of the tremendous leeway it gives them when adjusting the images after they are taken. Many digital cameras that shoot RAW photographs can also record a JPEG file, simultaneously giving the photographer the best of both worlds.
Since the first iPhone was released in 2007, digital photography apps in mobile phones have become very popular. As the results of the apps become more sophisticated, they are also becoming easier for the consumer to use. Hipstamatic, SnapChat, VSCO Cam, Snapseed, and Instagram are just several in the very long list of photo apps available for mobile phones.
Photography apps can be used to shoot, store, and manipulate images. In addition, most photo apps available for phones can be used to share images to popular online social media websites such as Facebook, Twitter, and Google+. Stand-alone photo sharing services such as Flickr, meant for photographers to store digital images, also have their own mobile photo apps for uploading and sharing images. One mobile photo application, Instagram, which launched in 2010, went on to dominate mobile photo sharing. The app quickly became very popular, and in 2012 Facebook purchased Instagram for 1 billion dollars. The simple photo app is used to take, filter, and share photos. Users can also tag friends and leave comments under photos. Users can chose to follow anyone who has made his or her account public. The U.S. singer Taylor Swift has the most popular personal account on Instagram with more than 55.7 million followers as of 2015. As of 2015 Instagram has more than 400 million users and has stored nearly 40 billion photos.