The Canon Electro-Optical-System, or EOS, autofocus (AF) 35mm and digital SLR cameras were first introduced by Canon in 1987 with the EOS 650. Cameras in the EOS system that are currently produced are all digital SLRs and primarily competes with the Nikon F series, as well as AF SLR cameras from Olympus, Pentax, Sony/Minolta and Panasonic/Leica.

The heart of the Canon EOS system is the EF lens mount. The EF lens mount replaced the previous FD lens mount and was designed with no mechanical linkages between moving parts in the lens and in the camera. The aperture and focus are controlled via electrical contacts.  Canon EOS cameras also feature eye-controlled focusing, quick control dials and multi-point autofocus systems.

Canon’s EOS cameras are marketed to a wide range of photographers at all experience and skill levels. Canon markets EOS models under different names in the Americas, Japan, and internationally. In North America, the Rebel, EOS digital Rebel XT and EOS Rebel T2 are for entry level photographers who want an easy to use, point and shoot style digital SLR. For the advanced amateur, Canon sells a number of Elan named models in the Americas, for example the EOS Elan 7N. For those shopping at the “premium” level, EOS models are named with a 1-digit model number, such as the EOS 3 and EOS 7D. Finally, at the professional level, Canon’s EOS line features more a more rugged and waterproofed build, 100% viewfinder field of view and faster performance. These models are named EOS-1D Mark II and EOS-1V, as examples. The last EOS line film camera, the EOS Rebel T2, was introduced in 2004 and there are no new film SLRs rumored in the EOS line.

The Canon EOS 550D (Rebel T2i) is fairly typical for the Canon EOS system and has the following features and specifications, for example:

• an 18 megapixel APS-C CMOS sensor
• increased sensitivity to light for low-light photography (ISO 100-6400 with expansion to 12800)
• a full HD movie recording (1920×1080)
• continuous shooting at speeds up to 3.7 frames per second
• a DIGIC 4 processor
• a 63-zone dual-layer TTL fll aperture metering system
• exposure compensation of +/- 5 stops in 1/3 or 1/2 stop increments
• shutter speeds up to 1/4000 of a second
• a built in flash
• 3.0 inch TFT color liquid crystal monitor
• Shoot JPEG, RAW (14-bit, Canon original), RAW+JPEG
• Self cleaning sensor unit
• Uses SD, SDHC, and SDXC memory cards (not included)
• The effective focal length multiplier (aka “crop factor”) is 1.6

At the higher end of the Canon EOS system is the Canon EOS-1D Mark IV, which has the following features and specifications:

• 16.1-megapixel APS-H CMOS sensor and Dual DIGIC 4 imaging processors
• 45-point Area AF sensor including 39 cross-type AF points with f/2.8 support
• ISO 100-12,800 for shooting from bright to dim light with low noise levels
• Continuous shooting at up to 10.0 frames per second with a buffer large enough to hold up to 121 JPG images (on fine setting) or 28 RAW images
• EOS HD movie with manual exposure control and multiple frame rates; 3.0-inch Clear View II LCD monitor
• Magnesium alloy body with shutter durability up to 300,000 cycles and exclusive dust-and-weather resistance
• Users can capture images to CF Card Type I and II, SD/SDHC (not included)
• The effective focal length multiplier (aka “crop factor”) is 1.3

Overall, the Canon EOS system is of superb quality. EOS cameras are easy to use, comfortable in hand and produce crisp, clean images. One of the best things about the Canon EOS line is that there is a model that will suit the needs of virtually every photographer.

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