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11-megapixel pro digital AF SLR delivers the goods We loved Canon's EOS-1d when we reviewed it a little over a year ago. Essentially a 4.48-megapixel digital version of the company's popular top-of-the-line EOS-1v pro AF 35mm film SLR, the EOS-1d offered pro features, pro performance and pro ruggedness. Now, meet generation II: the EOS-1Ds, which incorporates several advancements, the biggest being an 11.1-megapixel "full-frame" CMOS image sensor.  Eleven megapixels is serious resolution, enough to reproduce an image as a full two-page spread in a magazine like this one. Previous top-end pro digital SLRs produced images that could be reproduced only single-page size at 300 dpi. The EOS-1Ds also nicely solves a couple of other digital-SLR shortcomings. One is the "quasi-telephoto" factor: because the image sensors used in most digicams are considerably smaller than a full 24x36mm 35mm film frame, they capture a smaller portion of the image formed by any given lens, so you get the framing of a longer lens. This isn't bad for telephoto work, because it makes long lenses seem even longer (although it doesn't actually increase image magnification—it just crops the lens' image more). The problem is it also means your wide-angle lenses aren't nearly as wide as they are when used on a 35mm film camera—a 24mm lens used on the EOS D60, for example, provides the field of view of a 38mm lens used on a 35mm EOS model. The CMOS sensor in the EOS-1Ds has the same 24x36mm dimensions as a 35mm film frame (actually 23.8x35.8mm), so there's no "quasi-telephoto" effect: any lens used on the EOS-1Ds produces the same magnification and cropping as it does when used on an EOS 35mm film camera—and the EOS-1Ds will accept the full line of more than 50 Canon EF lenses. Another annoying digicam shortcoming has been the time lag between the moment you press the shutter button to make an exposure and the moment the exposure actually gets made. The EOS-1Ds' lag time is the same miniscule 55ms as the EOS-1v film camera's. As you can see from the accompanying pelican-taking-off shot, this digicam can react very quickly indeed. (The mirror blackout time after an exposure has also been improved, to just 87ms.) CMOS?
The EOS-1d uses a CCD (charge-coupled device) sensor, while the new EOS-1Ds (and Canon's lower-priced pro digital SLRs, the EOS D60 and its predecessor, the now-discontinued D30) use CMOS (complimentary metal oxide semiconductor) sensors. CMOS sensors use far less power than CCD sensors, produce less "noise" (which Canon's noise-reduction technology reduces even further in the EOS-1Ds), and cost less to manufacture. The perceived problem has been that CMOS sensors were also not as sharp as CCD sensors. A glance at a few blow-ups of EOS-1Ds images makes it clear that Canon has figured out how to get very sharp images with a CMOS sensor (after all, they've had a few years' experience at it). With the EOS-1Ds, you get sharp images with the color accuracy and wide dynamic range of pro slide films, plus all the historical advantages of CMOS. (Two imaging engines and three memory buffers also help attain speedy performance with those huge 11-megapixel image files.)  Camera Features
Like the EOS-1v (and original EOS-1d), the new EOS-1Ds is built for hard pro use, sharing the same rugged weather-resistant magnesium-alloy construction, with moisture seals at more than 70 points, and carbon-fiber-blade shutter tested to 150,000 exposures. And like those pro SLRs, the new EOS-1Ds features extremely quick and accurate autofocusing and exposure performance. The EOS-1Ds uses the same excellent AF system found in the EOS-1d and EOS-1v. It features 45 focusing points that cover a large 8x15mm elliptical area in the center of the image area, and includes 7 cross-type points down the middle. In One Shot AF mode the system utilizes all 45 points, focusing on the closest subject that falls under one of the points. You can "register" one of the points as your "home position," switching to it at the touch of a button. You can also select any of the 45 points yourself, set the camera to use only 11 or 9 of the 45 points for faster manual selection, or use Custom Function 17 to expand the AF area from a single manually selected point to that point plus 6 or 12 adjacent points. Pressing the AF-assist button and AF-point selection buttons simultaneously quickly selects the center AF point for spot autofocusing. (When you select spot metering, it will be linked to the selected AF point—a handy feature.) In One Shot AF (selected by pressing the AF button and rotating the main dial until One Shot appears on the LCD panel), the camera focuses on the subject, then locks focus there until you either make the shot or let go of the shutter button, and the shutter locks until focus has been achieved. In AI Servo AF, the camera continuously focuses as long as you keep the shutter button partially depressed, and you can make the exposure at any time. If the subject moves toward or away from the camera at a constant rate, predictive AF calculates the subject's position at the instant of exposure and sets focus accordingly. When the camera is set for AI Servo AF with automatic focusing-point selection, the camera will use the center AF point to establish focus, then automatically track the subject as it moves to another AF point. You can use Custom Function 20 to change the system's tracking sensitivity so that it won't try to focus on a passing obstruction that comes between the camera and the subject. Of course, you can also focus the lens manually (with USM lenses, you don't even have to switch to manual mode—just rotate the lens' focusing ring). The EOS-1Ds accepts all 10 user-interchangeable focusing screens introduced with the EOS-1v, including several with manual-focusing aids. Personal Function 16 lets you prefocus manually at a predetermined distance, and the camera will automatically fire when a subject arrives at that distance.
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