Thursday, June 21, 2007
Canon Releases The EOS-1D Mark III Digital SLR
Advanced Autofocus Technology
The brand-new autofocus system in the EOS-1D Mark III Digital SLR represents a complete reconsideration of professional AF. Like previous EOS 1-Series Canon cameras, the EOS-1D Mark III Digital SLR has 45 AF points, but unlike its predecessors, 19 of them, rather than seven, are of the high-precision cross-type configuration. In addition to the center point, the new array allows the other points to be divided into groups of nine inner and nine outer focusing points plus a center point, which makes picking an individual focusing point much faster and easier than going through all 45, as in the past. During manual AF point selection, the AF point area is expandable. At the request of sports and wildlife photographers, a new micro-adjustment feature allows for very fine changes in the AF point of focus for each lens type in use, along with the addition of adjustable focus-tracking sensitivity as another sophisticated new AF feature. In addition to the AF sensor itself, other new components in the AF system include the reconfigured concave submirror and the secondary image formation lens, both products of Canon's vast expertise in optical engineering. Last but not least, the low-light sensitivity of the new AF sensor has been doubled to EV-1 for superior performance compared to earlier EOS digital SLRs.
Twice as Smart With Dual DIGIC III Image Processors
To cope with the voluminous signal processing required by the EOS-1D Mark III Digital SLR's 10.1 megapixel resolution and top continuous shooting speed of 10 fps, Dual DIGIC III imaging engines are incorporated for parallel signal processing. The DIGIC III image processor replaces the DIGIC II and assists in rendering very fine image detail and natural color reproduction with 50 percent less shadow noise than previous EOS digital SLRs. The CMOS sensor reads out to the dual DIGIC III processors simultaneously in eight channels. By having two processors handle the workload, image processing is now approximately 1.5x faster; Compact Flash access speed is now 1.3x faster and SD card access is now 2x faster. The EOS-1D Mark III Digital SLR is compatible with the new high-capacity SDHC format memory card. The extra power of dual DIGIC III processors has also allowed analog-to-digital conversion to improve from 12 to 14 bits per channel, meaning that tonal gradation for RAW images is now divided into 16,384 separate levels per channel rather than 4,096. The difference can be seen in the superb prints and magazine spreads the EOS-1D Mark III Digital SLR makes, as well as, in its freedom from defects such as moirés.
The Canon Proprietary CMOS Sensor
The all new, 10.1 megapixel CMOS sensor is designed and manufactured by Canon using semiconductor manufacturing equipment that is designed and manufactured by Canon, allowing synergies that are unique in all of photography. The sensor is APS-H size, 28.1 by 18.7mm, significantly larger than the much more commonly found APS-C, usually about 23.5 by 15.5mm. The lens magnification factor is 1.3x, rather than 1.5x or 1.6x. The increased sensor size means that each pixel can be larger for a given resolution. The pixels of the EOS-1D Mark III Digital SLR are 7.2 microns square. A sensor with 10 megapixels in APS-C size would have pixels less than 6 microns square, smaller and therefore receiving less light, requiring more amplification and producing more noise. The comparison is even more favorable to the EOS-1D Mark III Digital SLR because Canon's intense involvement with sensor technology has enabled it to increase the proportion of each pixel that is sensitive to light, called the fill factor, so its pixels are not only bigger, but also more receptive to light. Yet another improvement comes from the revised microlens array that collects light for the sensor. The new unit has smaller gaps between the tiny lenses, meaning more light is gathered and less is lost. All of this helps to explain the sensational low-light performance of the EOS-1D Mark III Digital SLR and the terrific quality of images shot at ISO 3200 and 6400.
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