Digital Cameras
A digital camera is an electronic device used to transform images into electronic data. Modern compact digital cameras are typically multifunctional, with some devices cabable of taking photographs, video, and/or sound. 2005 saw a dramatic increase in consumer adoption of digital cameras as opposed to 35mm film cameras. North American sales of their digital counterpart exceeded, for the first time in history, sales of film cameras.
Early History
Digital cameras, in the sense of a device meant to be carried and used like a handheld film camera, appeared in 1981 with the demonstration of the Sony Mavica (Magnetic Video Camera). This is not to be confused with the later cameras by Sony that also bore the Mavica name. This was an analog camera that recorded to a 2 inch by 2 inch "video floppy". In essence it was an analog video camera that recorded single frames, 50 per disk in field mode and 25 per disk in frame mode. The image quality was considered equal to that of then-current televisions.
Analog cameras do not appear to have reached the market until 1986 with the Canon RC-701. Canon had used this model to capture images at the 1984 Olympics. Several factors held back their widespread adoption; the cost (upwards of $20,000), poor image quality compared to film, and the lack of quality affordable printers. Capturing and printing an image originally required access to equipment such as a frame grabber, which was beyond the reach of the average consumer. The "video floppy" disks later had several reader devices available for viewing on a screen, but were never standardized as a computer drive.
The early adopters tended to be in the news media, where the cost was negated by the utility and the ability to transmit images by telephone lines. The poor image quality was offset by the low resolution of newspaper graphics. This capability to transmit images without a satellite link was useful during the Tianenman Square uprising in 1989 and the first Gulf War in 1991.
The first analog camera marketed to consumers may have been the Canon RC-250 Xapshot in 1988. A notable analog camera produced the same year was the Nikon QV-1000C, which sold approximately 100 units an recorded in greyscale. It's image quality in newspaper print was equal to film cameras, and in appearance it closely resembled a modern digital SLR.
The Arrival of True Digital Cameras
The first true digital camera, that recorded images as a computerized file, was likely the Fuji DS-1P of 1988, which recorded to a 16MB internal memory card which used a battery to keep the data in memory. This camera was never marketed in the United States. The first commercially available digital camera was the 1991 Kodak DCS-100, the beginning of a long line of professional SLR cameras that were based in part on film bodies, often Nikons. It used a 1.3 megapixel sensor and was priced at $13,000.
The move to digital formats was helped by the formation of the first JPEG and MPEG standards in 1988, which allowed image and video files to be compressed for storage. The first consumer camera with an LCD display on the back was the Casio QV-10 in 1995, and the first camera to used compact flash was the Kodak DC-25 in 1996.
The marketplace for consumer digital cameras was originally low resolution (either analog or digital) cameras built for utility, in 1997 the first megapixel cameras for consumers were marketed. The first camera that offered the ability to record video clips may have been the Rioch RDC-1 in 1995.
1999 saw the introduction of the Nikon D1, a 2.74 megapixel camera that was the first digital SLR developed entirely by a major manufacturer, and at a cost of under $6,000 at introduction was affordable by professional photographers and high end consumers. This camera also used Nikon F-mount lenses, which meant film photographers could use many of the same lenses they already owned.
2003 saw the introduction of the Canon Digital Rebel, a 6 megapixel camera and the first digital SLR priced under $1,000, and thus affordable to consumers.
Connectivity
Many digital cameras can connect directly to a computer to transfer data. Early cameras used the PC serial port. USB is now the most widely used method, though some have a FireWire port or use Bluetooth. Most cameras are viewable as USB Mass Storage but earlier ones used Picture Transfer Protocol or proprietary protocols requiring software from the manufacturer. Some cameras such as the Kodak EasyShare One are able to connect to computer networks wirelessly via 802.11 Wi-Fi.
Increasingly popular is the use of a card reader which may be capable of reading several types of storage media, and transferring at high speed to the computer. This also avoids draining the camera battery during the download process as the device takes power from the USB port.
Integrated Devices
Some devices, like mobile phones and PDAs, contain integrated digital cameras. Mobile phone cameras are even more common than standalone digital cameras.
Storage
Digital cameras need memory to store data. A wide variety of storage media has been used. These include:
- Onboard flash memory: Cheap cameras and cameras secondary to the device's main use (such as a camera phone).
- Compact Flash cards/Microdrives: Typically higher end professional cameras. The microdrives are actual hard drives in the compact flash form factor. Adapters exist to allow using SD cards in a compact flash device
- 3 1/2 inch floppy disks: Mainly the Sony Mavica line of the late 1990's.
- Memory Stick: A proprietary memory type manufactured by Sony.
- PCMCIA hard drives: Early professional cameras, discontinued.
- Mini CDR: a 185MB small form factor CD, most commonly seen in the Sony CD-1000.
- SD/MMC Card: A flash memory in a small form factor that is gradually supplanting compact flash.
- Thermal printer: Known only in one model of camera that printed images immediately rather than storing.
- xD Picture Card: Developed by Fuji and Olympus in 2002, a format smaller than an SD card.
- Smart Media: a now obsolete format that competed with Compact Flash, and were limited to 128MC in capacity. One of the major differences was that Smart Media had the memory controller built in the reading device, while in Compact Flash it was in the card. The developed replacement for Smart Media was the xD card.
- FP Memory: A 2-4MB serial flash memory, known from the Mustek/Relisys Dimera low end cameras.
- Video Floppy: A 2 inch by 2 inch floppy disk used for early analog cameras.