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The Canon EOS 30D takes up where the 20D left off. Strikingly similar to the camera it replaces, the EOS 30D offers a larger LCD monitor, refinements in areas such as metering, burst speed and duty cycle of the shutter mechanism, and a number of minor improvements to the functionality of the camera.
Aside from minor changes to the back of the camera to accommodate the larger screen and an new Print button (see further), the EOS 30D is identical to its predecessor. The 30D's body is built has a stainless steel chassis, covered in a magnesium alloy mixed with textured, high strength, flat black poly carbonate with rubberized areas on the right side both front and back. 
The 2-stage shutter release tops the rubber-clad grip, and is placed in a area shaped for the index finger.
Directly behind the shutter release is the Main Dial, which is used mostly to select shooting-related settings including aperture and shutter speed when the camera is set to one of the advanced modes.
Nearby, to the right in the image shown here, is the lamp used for Red-eye Reduction and the Self-timer.
A row of 4 buttons is aligned above the LCD Panel. The first on the left is a bit smaller than the others: 
Serves to illuminate the LCD panel. Pressed once the panel lights for approximately 6 seconds. If any other control is used, the illumination time is extended. And when pressed again, the button turns off the light.
The other three buttons have dual functions, as indicated by their labels. Once any one of these buttons is pressed, the specific function is selected using either: * the Main dial 
, * or the Quick Control dial 
which is positioned near the top right of the LCD monitor on the back of the camera (see further): 
When used with Main Dial the button allows selecting one of the three Auto Focus modes: * One Shot AF: focuses when the shutter button is pressed halfway. If needed the shutter button can be maintained half pressed to maintain focus while the shot is recomposed. * AI Servo: maintains focus on a moving subject while the camera's shutter button is maintained halfway. The system includes predictive AF which is able to track a steadily moving subject as it approaches or retreats form the camera. * AI Focus: automatically switches when needed from One Shot AF to AI Servo.
When used in conjunction with the Quick Control Dial , the button serves to select the White Balance: * Auto: 3000 to 7000 K * Daylight: 5200 K * Shade: 7000 K * Cloudy, Twilight, Sunset: 6000 K * Tungsten (incandescent): 3200 K * White Fluorescent Light: 4000 K * Flash: 6000 K * Custom (user selectable under ambient light): 2000 to 10000 K * Colour Temperature (set in degrees Kelvin): 2800 to 10000 K 
Selects the Drive mode when the Main Dial is used: * 
Single Shooting: the camera captures a single shot every time the shutter release is pressed. * 
Continuous Shooting: captures photos continuously at up to 5 shots per second, for up to 30 shots (Large/Fine JPEG) or 11 RAW shots. * Low Speed Continuous Shooting captures photos at 3 frames per second for up to 37 consecutive shots (Large/Fine JPEG). * 
Self Timer Operation: provides a 10-second delay before the shutter is released. 
Selects the ISO sensitivity when the Quick Control Dial is used: 100, 200, 400, 800, or 1600 ISO; extendable to 3200 ISO. In the Basic Zone (see further) the ISO is set automatically between 100 and 400 ISO. 
Selects the Metering mode when the Main Dial is used: * 
Evaluative Metering: is the camera's standard metering mode, and can even be used for backlit subjects. * 
Partial Metering: meters an area covering approximately 9% of the viewfinder, at the centre of the frame. * 
Centre-Weighted Metering: meters the entire frame, but gives greater importance to centre of the frame. * 
Spot Metering covers an area approximately 3.5% of the viewfinder at the centre of the frame, and is new on the EOS 30D.
The same control serves to set Flash Exposure Compensation when the Quick Control Dial is used. Flash exposures can be compensated in 1/3 EV or 1/2 EV increments over ±2EV, and the compensation setting is retained after the camera is turned off. Moreover, flash compensation applies not only to the 30D's built-in flash, but also to any EOS-dedicated EX-series Canon Speedlite. 
The LCD Panel that is behind these buttons serves as the main interface between the user and the camera, relaying clear and detailed information about the EOS 30D's current settings.
The LCD panel is able to provide a great deal of information, some of it using the characters at the top of the panel which can display messages such as buSY or FuLL CF: * Shutter speed * ISO * White balance * White balance correction * Battery check * Beeper * Custom function * Red-eye reduction * Flash exposure compensation * Image quality and size * Metering mode * Exposure level * Aperture * AF point selection * Error messages * Processing parameters * Shots remaining * Self-timer countdown * Bulb exposure time * Monochrome shooting * Drive mode * Auto exposure bracketing * AF mode * CF card writing status
The TTL viewfinder of the EOS 30D shows 95% of the frame horizontally and vertically, and has an eyepoint of 20mm. A dioptric adjustment (-3 to +1 diopter) is available on the top right side of the exit pupil, behind the soft, rubber-trimmed eyepiece that can be removed to attach the eyepiece cover during long exposures. The focusing screen, precision matte, is fixed and does not offer on-demand composition guidelines, but the image is very crisp and bright. The 9 AF points of the camera are etched in black and light up in red when active, and can be selected using the Multi-Controller (see further). 
The viewfinder information is presented in green, and although it shows only relevant settings, it indicates shutter speed, aperture, AE lock and AEB in-progress, 
exposure level, metering, exposure warning, flash ready and Improper FE lock warning, red-eye reduction lamp, high-speed synch, FE lock, High Speed Flash, FEB in progress, flash exposure compensation, white balance correction, maximum burst, and memory card info such as Card Full, No CF Card, and CF Card Error. Mode Dial. As is common with Canon cameras, the Mode Dial is divided into 2 areas. One area is called the Basic Zone, and includes the Auto mode in addition to the scene modes which are part of the Image Zone. The modes in this zone share some common features like the automatic release of the flash when the mode allows it and if it is needed, and the use of Auto sensitivity from 100 to 400 ISO. The other area of the dial is the Creative Zone, and it covers the more advanced shooting modes: P, Tv, Av, M and A-DEP.
The Auto mode is the division between the two zones: 
Set to Auto the EOS 30D is as simple to operate as a point and shoot camera, and a number of the external buttons are disabled (autofocus and white balance selection, ISO, metering, compensation, continuous mode, etc). With the Auto mode, metering is set to Evaluative, a 9-point wide area autofocus, and sensitivity (ISO) to Auto, allowing the camera to adjust it over a range of 100 to 400 ISO.
The Image zone contains 6 Scene modes. As with the Auto mode, the camera controls all parameters including CCD sensitivity (100-400 ISO), and most external controls are purposefully disabled to prevent the scene-specific camera settings from being unintentionally altered: 
Portrait mode selects a wide aperture to blur the background of the subject. The pop-up flash is automatically controlled, while the Drive mode is set to Continuous shooting, the AF mode to One Shot, and the metering to Evaluative metering. 
Landscape mode selects small apertures to maximize depth of field. This mode prevents the release of the flash, sets the camera to Single shooting and uses Evaluative metering. This mode can also be used to shoot a night scene as it offers a maximum 8-second exposure time. 
Close-up mode works to balance the depth of field and the shutter speed, but with an overall preference for a shallow depth of field. This mode also controls the release of the pop-up flash, and uses Single shooting. 
Sports mode optimizes the shutter speed so as to freeze action. The pop-up flash cannot be released, the Continuous shooting mode is activated, as is the AI Servo mode which allows the camera to track the subject and maintain focus using all 9 AF points. 
Night Portrait mode uses a longer exposure and flash to capture a well-lit foreground and a visible background. The flash is automatically opened and only the Single or Self-timer/Remote control drive modes are available. The mode automatically uses Evaluative metering, Single shooting and One Shot AF. 
Flash Off mode prevents the flash from being opened automatically and can be used for interior shots, or long exposures (5-second maximum exposure time, controlled by the camera).
The Creative zone, on the other side of the Auto mode, starts with the Program mode: 
The Program mode chooses the most appropriate combination of shutter speed and aperture, and displays it in the viewfinder's display. Program Shift is also available, and another combination of aperture/shutter speed can be selected using the Main Dial . 
Shutter Priority mode, Tv, provides access to the full shutter speed range of the EOS 30D: from 1/8000 sec to 30 seconds with the Main Dial , while the camera sets the aperture. 
Aperture Priority mode, Av, allows selecting the aperture, using the Main Dial while the camera matches the selection to a shutter speed. The range depends on the lens in use. Depth of field preview is available by pressing on a button located on the lower left side of the lens mount of the body, beneath the larger lens release button. 
Manual mode provides control over the shutter speed using Main Dial , and the aperture using the Quick Control Dial . The aperture range depends on the lens in use, the shutter speed range covers from 1/8000 second to 30 seconds, and adds a Bulb mode that is unlimited, and which can be used in conjunction with mirror lock-up, and a Long Exposure Noise Reduction option (see the Characteristics section of the review). 
Automatic Depth of Field AE works much like the Program mode, but serves to obtain a wide depth of field between a near and a far subject, and is effective for group photos and landscape shots. The camera uses all 9 focusing points to determine the nearest and the farthest points in the frame and sets the aperture accordingly.
Six buttons are arranged below the Mode Dial, on the left side of the 2.5-inch, 230,000 pixel LCD monitor, the uppermost being immediately to the left of the viewfinder: 
New on the 30D, the Print/Share button can be used to make a print of the image under review when the 30D is connected to a PictBridge, Canon CP Direct, or Bubble Jet Direct printer via USB, or to start the transfer of images to a computer when connected to one that is running the Canon software supplied with the camera. Either during printing or image transfer, a blue LED at the centre of this button blinks. MENU
Calls up the menu of the 30D. The menu is composed of three main sections that flow from one to the next looping back to the beginning once the last option of the third section has been reached. (See the Characteristics section of the review for more details.) INFO
With the camera set to a capture mode, pressing the INFO button displays a screen that summarize the current menu settings. The display shows the date and time, the picture style including detailed settings for the style, the colour space in use, white balance shift and exposure bracketing, colour temperature setting, ISO speed, auto rotate setting, auto power off, flash exposure compensation, CF card remaining capacity, and even indicates when a wireless transfer of images has failed while using the optional WFT-E1/E1A wireless file transmitter. 
In Playback the button controls the quantity of information superimposed on the monitor. One presentation superimposes a grey box on the lower left of the screen, showing shutter speed, aperture and the image's position amongst those contained in the current folder. Pressing the INFO button once switches the presentation to a display with the thumbnail, a histogram of the image, and the most pertinent shooting data below. Should any part of the image be overexposed, the area appears as flashing. Pressing the button once more removes all superimposed data, leaving only the image.
The next three buttons are only effective when the camera is set to the Playback mode: JUMP When pressed the JUMP button serves to jump images in groups of 10 images, or 100 images, or jump to a shot date forwards or backwards. When the thumbnail view is selected (9 pictures per screen), the JUMP button jumps 9 images at a time, and when the image is magnified on the monitor (see further) the jump maintains the same magnification level and position. 
Starts the playback mode. 
Deletes one image at a time, or all images.
Six more controls are positioned on the right side of the monitor. Starting in the upper right corner of the EOS 30D's back, two buttons control capture and playback related functions.
On the left side: 
serves to lock the Auto Exposure (AE-Lock) or the Flash Exposure (FE-Lock) if the flash is raised or an EX-series Canon Speedlite is mounted on the camera. 
In Playback, the button serves to display an index (9 thumbnails per screen) of the photos on the card, or zoom out of a photo that has been magnified for a closer look.
On the right side: 
serves to select the focus point when the camera is set to P, Tv, Av, and M modes, any one of 9 AF points can be selected manually by pressing this button, and then using the Multi-controller (see further), which is a joystick-like control. 
In the Playback mode, the same button can be used to magnify an image up to 10X, while the Multi-controller serves to move around the image. In addition during the magnified view the Main Dial [] or the Quick Dial [] can be used to move to the next image, forwards or backwards, and see it at the same magnification and position.
The Multi-controller comes next. It is a small joystick that can be moved around in eight distinct directions, or be clicked just like a mouse button. It serves to move around on a magnified image, or select the focus point when the camera is set to P, Tv, Av, or M modes, and return the focus point to the centre when clicked. 
The Quick Control Dial is the large wheel directly below. By default it serves to review images, navigate the menu, set the aperture in the Manual mode, or set exposure compensation However, if so selected in Custom settings (see the Characteristics section of the review for more information about Custom settings), it can be used to setting the exposure compensation (±2EV in in either 1/3 or 1/2 increments) when the 30D is set to P and A-DEP modes. Alternatively, it can be used to select the focus point by cycling through each AF point in turn, when so set in the Custom menu.
The small button labelled SET in the middle of the dial serve to confirm the selection of specific settings for options. In addition it can be set, again in the Custom Settings, to immediately access a pre-chosen function such as the image quality, picture style, menu display, or image replay.
The last external control on the back of the EOS 30D is the Power Switch. The switch has three positions: OFF, ON, and 
which indicates ON with the Quick Control Dial operational.
The only remaining external controls of the EOS 30D are on the right side of the lens mount. At the top, is the Flash Release button, used only when the 30D is set to P, Tv, Av, or M modes (see below).
The large rectangular button below is the lens release. The EOS 30D is compatible with EF and EF-S lenses.
And at the bottom is the Depth of Field Preview button, which stops down the lens from the brightest aperture that is used for the viewfinder to the aperture selected by either the camera or the user, and reveals the depth of field which will be visible in the image. 
The built-in flash of the 30D opens automatically when the camera is set to a Basic zone mode, with the exception of the Sports, Landscape, and Flash Off modes. While with the Creative zone programs it must be released manually.
Flash metering is E-TTL II autoflash, and is fully compatible with Canon Speedlites that can be mounted on the hotshoe above the prism housing. The pop-up flash has a Guide No. of 13/43 (meters/feet) at 100 ISO, and a recycle time of approximately 3 second. The flash covers a 17mm focal length. Since the external differences between the EOS 20D and the 30D are minor, our comments about the ergonomic design of the camera remain similar to our observations about the 20D. The first is that the power switch requires the use of the left hand and even with familiarity with the camera, is not as fast and efficient as a grip or shutter mounted power switch. The second is that the position of the red-eye reduction lamp/self-timer light can be partially masked while holding the camera or by a larger lens, which lessens its effectiveness. It would have been better placed near the flash.
Author: http://www.megapixel.net
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