Manual Control Options
The EOS 5D is marketed to advanced hobbyists and professionals – a group that requires control over their images. The 5D offers a hefty set of manual options to meet their needs. Aperture, shutter speed, focus, ISO, white balance metering, image size and compression, drive mode, exposure compensation, and camera setup are all available to the photographer. More advanced options are also accessible, such as color space selection, image parameters (labeled Picture Styles), flash mode, custom settings, interchangeable focusing screens, and button allotment. For most settings even the increment of alterations can be determined by the user. The Canon 5D provides users with all expected manual controls as well as the ability to customize the camera to their shooting style.
Focus
Auto Focus (8.0)
The Canon 5D features a newly designed autofocus system. Building off the 9-point configuration of the 20D, the 5D adds 6 supplemental focusing sites, a new AF algorithm, and new circuitry. The nine visible autofocus sensor sites are displayed in the same horizontal-diamond array within the viewfinder as the 20D and are all tightly clustered near the center of the frame. The farthest left and right sensors are still inside the middle half of the viewfinder, and the rest of them are inside the middle 25 percent. The sensors are tightly packed vertically, as well.
The nine visible sensor sites are designed to work with lenses with maximum apertures as small as f/5.6, while two of the six supplemental sensors are designed to focus f/2.8 and faster lenses more accurately. These sensors are arranged vertically, near the center of the frame. The four other supplemental sensors help improve focus of moving objects when the camera is set to AI SERVO. They're between the center sites and the intermediate ones. These additional sites are active when the camera is set to automatically select the active sensor site or when AF point selection is expanded using the custom function (C.Fn-17-1).
The Canon 5D has three autofocus modes: Single Shot focuses when the shutter release is pressed halfway, and keeps that focus until the user lets up on the release; Predictive AI SERVO AF focuses continuously, and detects motion to maintain focus on moving subjects; and AI Focus AF automatically switches between Single Shot and Servo.
There is also a setting within the custom functions to configure the selection of the camera’s AF points. The default setting requires users to hold the AF button and rotate the jog dial; however, this action can be shifted over to either the small multi-controller or large Quick Controller.
In practice, the 5D’s AF was much more adept than the 20D’s, particularly when the desired subject was a dark tonal value. When focusing on a low contrast object of lighter tonal values, the 20D’s performance was much more in line with the Canon 5D’s, though still not quite as good. In moderate lighting, AF on the 5D snapped in quickly and was almost as fast as the AF on the 1D Mark II n until the cameras were turned vertically. In vertical shots, the 1D Mark II n definitely showed its edge. However, for a potentially sub-$3000 camera, the low light autofocusing capabilities of the EOS 5D were strong. In low light scenes with high contrast, the 5D was able to pick out objects in less than 3 lux of illumination – which is impressive.
Manual Focus (8.0)
Like other DSLRs, the Canon 5D allows manual focus. The standard focusing screen is full of contrast and bright, but Canon offers two other focusing screens that can be interchanged by the user. See the ‘Viewfinder’ subsection of ‘Components’ for further elaboration on focusing screens.
Exposure (8.5)
The Canon 5D offers a full manual mode, in which everything is set by the user. The 5D also offers Aperture priority, Shutter priority, Program mode (it can be shifted), autoflash mode, Full Auto mode, and a Custom or user defined mode.
Exposure compensation is available in a +/- 2 stop range in either 1/3 or 1/2-stop increments as well as Auto Exposure Bracketing, also offered in a +/-2 stop range in 1/2 or 1/3-stop increments.
Metering (8.25)
The Canon 5D contains the same 35-zone TTL metering system that the EOS 20D employs, but offers a more complete range of functions. Along with an evaluative metering system that links to the autofocus sites, there is an 8 percent Partial metering mode, center-weighted averaging, and a 3.5 percent spot metering mode. The EOS 5D defaults to the evaluative pattern.
Canon’s evaluative metering system produced good results in our tests and the addition of a spot metering mode (absent on the EOS 20D) will be of great assistance in scenes with high contrast or strong backlighting.
White Balance (9.25)
The Canon 5D offers a very comprehensive list of color balance alternatives. There are six white balance presets, plus custom and auto settings. The six presets are: Daylight, Shade, Cloudy/Twilight/Sunset, Tungsten, White Fluorescent, and Flash. For custom settings, the user calibrates the camera to an image of a white card that has been previously recorded. This method may 
appear a bit more cumbersome than the instant custom set method employed by most DSLRs; however, it acts as a memory, conserving time when shooting in multiple (fixed) lighting setups. It's also possible to simply dial in a setting in degrees Kelvin between 2,800 and 10,000, in 100-degree increments. Any of the white balance settings can be fine-tuned, on a Green to Magenta axis and a Blue to Amber axis. Each axis has nine increments. The Canon 5D also offers white balance bracketing, and can combine white balance and exposure bracketing. Bracketing is available with RAW images.
ISO (8.75)
The Canon 5D's basic ISO range is from 100 to 1600, in 1/3-stop steps. It offers a range down to ISO 50 and up to 3200 in extended mode. The 1/3-stop incremental range offers precise selections and enables users to control noise in the shot. It is certainly appropriate for a professional DSLR.
Shutter Speed (9.0)
The Canon 5D's shutter runs from 30 seconds to 1/8000th of a second. It also has a Bulb option for longer exposures. The 5D can sync external flashes at up to 1/200 of a second.
Aperture (0.0)
The Canon 5D is not marketed with a specific lens; the available aperture range will be dependant on the applied lens.
