Chapter Three: Managing Dials, Buttons, Switches, and a Joystick
When you look at the body of the EOS 5D Mk III, it’s easy to be impressed with the number of “control devices” Canon has been able to crowd onto the top, front, and back of this camera. And then you learn that several of the controls are capable of being given new personalities, greatly expanding the number of adjustments you can make to customize the camera to your own style and needs. Just don’t hand your camera off to another photographer without a warning if you’ve made changes to the default actions. At a minimum, the photographer will be frustrated because all the setup sequences he knows won’t work and worse, if he modifies your setup to conform to how he normally works, you’ll lose the efficiency you so carefully created, and possibly a friend as well.
The Dials
The EOS 5D Mk III features two multi-purpose dials and one single-purpose dial. There’s also the dioptric adjustment knob, which is really a dial, though it does nothing that would directly affect the result of an image capture. The Main Dial and the Quick Control Dial are used for a variety of purposes, depending on the context of the moment, but the Mode Dial serves the singular purpose of allowing you to choose which one of the several basic camera functions you want to start with.
The Mode Dial
The Mode Dial also includes a button in the center of the dial that must be depressed before the Mode Dial can be rotated. In figure 3-1 the red arrow points to a white index mark on the side of the reflex housing next to the Mode Dial. Once you’ve determined what setting you want to use, press the button in the center of the Mode Dial, then rotate the dial so that your desired setting is positioned at the index mark. The Mode Dial can be set regardless of the camera’s power switch setting.
Figure 3-1. Mode Dial with index
The Main Dial
The Main Dial has two different states that it will recognize. If you have not pressed a function button in the preceding six seconds, then rotating the Main Dial will change the aperture if the Mode Dial is in the Av (aperture value) position, or it will change the shutter speed if the Mode Dial is in the Tv (time value) position. If the Mode Dial is in the P (program) position, and no other button has been pressed in the preceding six seconds, pressing the shutter button halfway then rotating the Main Dial will cause both the aperture and the shutter-speed setting to be changed, within the limits of the set ISO speed. If you have set the ISO to Auto, then determining the ISO is done when you press the shutter button halfway just prior to rotating the Main Dial (but, on my camera anyway, you get only four seconds between pressing the shutter button and starting the Main Dial rotation).
The Main Dial is also a major means of navigating menus or the Quick Control screen, generally in a horizontal direction. (The Quick Control Dial is used for the vertical navigation in those cases.)
For many of the buttons on the camera, the Main Dial, often in conjunction with a complementary action from the Quick Control Dial, allows you to identify a specific option provided by that button; pressing the SET button then activates the function of that option. There are some exceptions that aren’t obvious. For example, while you’re in playback mode, either the Quick Control Dial or the Main Dial will allow you to scroll through the images in a folder on the memory card. The SET button would have no effect on this operation.
In many cases, you will need to give attention to the LCD monitor: if the monitor shows an icon like 
, then the Main Dial will be used to make adjustments. An example of this is when you’re in playback and want to magnify a portion of the image. You press the magnify button, but must rotate the Main Dial clockwise (as determined from the back of the camera) to enlarge the image. If you rotate the Main Dial counterclockwise from that initial starting position, at the first increment you will see thumbnails of four images, with the current image surrounded by a blue border. The second increment displays nine image thumbnails.
There are three dual-purpose buttons across the top of the LCD panel. When pressed, each button is active for six seconds, awaiting dial input from you. Each function on these buttons needs only one level of input, so that allows the Main Dial to be used for controlling the selection of values available for the function associated with the left half of the button identifier (e.g., ISO, on the right-most of these three buttons) while the Quick Control Dial is used for the other function on that button (flash exposure compensation, in this case).
The Quick Control Dial
The Quick Control Dial works in conjunction with the Main Dial. Occasionally, as when using a dial to scroll through a series of images in playback or through the characters on the “keyboard” for creating Copyright Information on the SET UP4 menu, you can use either. But in most instances, the Quick Control Dial is used to navigate vertically through a list of menu options while the Main Dial navigates horizontally across menus.
Figure 3-3. The Quick Control Dial
As noted in the section describing the Main Dial, when you are changing settings for one of the dual-purpose buttons, the Quick Control Dial provides the scrolling of options for the right-hand icon on the dual-purpose button.
There are a few instances in which two variables are displayed on the same screen, an example being the Exposure Compensation/Automatic Exposure Bracketing screen from the SHOOT2 menu. On that screen, rotating the Quick Control Dial adjusts the Exposure Compensation setting, and the Main Dial is used to adjust the Automatic Exposure Bracketing setting. If in doubt as to which dial controls what, look at the right end of the two scales for the icon of the controlling dial: for the Main Dial, and 
for the Quick Control Dial.
The Dioptric Adjustment Knob
The Dioptric Adjustment knob is the means by which you customize the view through the viewfinder to match your own eyes. If you are a glasses wearer, you will probably want to determine whether you compose and focus with or without your glasses. The dioptric adjustment has no way to dynamically determine whether you are wearing glasses, and there’s no mechanism for storing a “with glasses” setting and a “without glasses” setting. As I compose and focus both with and without my glasses, I’ve adjusted for one, then note the number (and direction!) of clicks to the other position. In that way, I can fairly quickly set the dioptric adjustment to give me the sharpest possible view, regardless of whether I’m wearing glasses. That’s another of those private, individual settings that may make you reluctant to hand your camera off to another photographer.
Figure 3-4. The Dioptric Adjustment Knob
The Buttons
The Quick Control Button
The Quick Control button brings up the Quick Control screen when the camera is in still-image shooting mode. If the camera is in playback mode, there is a playback-oriented customized Quick Control screen (actually, more of an overlay on whatever is already on the LCD monitor), and when in Movie mode, there is yet another customized Quick Control overlay. There’s even a customized, though brief, Quick Control overlay for Live View mode. The intent of the Quick Control button is to give you immediate access to options that relate to your current activity. If the camera has shut down the meters, pressing the Quick Control button is ignored even when the power switch is still on. To make it active, press the shutter button halfway and then press the Quick Control button again. Otherwise, you can be in the middle of almost anything and press the Quick Control button to open a Quick Control screen.
Figure 3-5. The Quick Control Button
While in the Quick Control screen or one of the overlays, you can navigate between options with the Multi-controller’s joystick, though selection of a value for an option is done with the Quick Control Dial or the Main Dial. When shooting still images, once an option is selected, you can “dial in” a value if you know what the variables are, or—with the option selected—press the SET button to open a setting screen dedicated to that option and its variables. Though you must use the Multi-controller’s joystick to select the option, you cannot use the Multi-controller’s center button to open an option’s setting screen; only the SET button will do that.
The Magnify Button
The Magnify button is important when playing back images and when shooting in Live View mode. The navigation is much the same for both. During image playback (or while viewing a scene in Live View), press the magnify button to start the magnification functions.
Figure 3-6. The Magnify Button
During playback, you have access to all the images on the memory card. You may find it helps to view several thumbnails at a time to locate a specific image. If that’s the case, then rotate the Main Dial counterclockwise one notch to view four thumbnails at once, or two notches to view nine thumbnails at once. The Quick Control Dial is used for selecting the “next” image; if not currently displayed as a thumbnail, then the next image on the memory card is brought in and displayed as a thumbnail.
When you use the magnify button to enlarge an image from the memory card, you can rotate the Main Dial to change the magnification of the display by roughly 1.5x to 10x. That in itself is of no value unless the portion of the original image that you wanted to see enlarged just happens to fall dead center in the image. Otherwise, use the Multi-controller joystick to reposition the white rectangle in the white outline, showing the relative location being displayed on the LCD monitor.
With an image being composed on the LCD monitor while in Live View mode, you can press the magnify button to enlarge the image 5x and press the button again for 10x enlargement. Pressing the magnify button a third time results in the enlargement returning to 1x. As when using the magnify button during image playback, you can use the Multi-controller joystick to move the enlarged image, which allows you to select the critical part of the composition without it having to be dead center. There is a small white rectangle inside a white border that represents the relative portion of the full image that is being displayed. For macro photography or any photography that would benefit from being able to use an enlarged image for critical focusing, the combination of Live View and magnificatio n is truly noteworthy. Be aware, though, that the image you’re seeing on the LCD monitor is a simulated image and can appear sharper than the final recorded image. Even so, you can use it to achieve the sharpest possible capture.
The Shutter Button
The Shutter button has acquired some significant responsibilities over the years. In the days of the Kodak box camera, taking a picture was a three-step process: you looked in the viewfinder to compose the picture, pressed the shutter-release button to expose the film, and wound the film to the next frame.
Figure 3-7. The Shutter Button
In the EOS 5D Mk III, the shutter button performs two critical functions. First, pressing the button halfway turns on the exposure and autofocus meters, allowing the camera to determine whether the selected aperture, shutter speed, and ISO will permit a good exposure. The camera will also attempt to achieve focus based on a number of options you have specified and in a mode you’ve selected. There are computers in most of the lenses we use today, and there are computers in the camera. If you have an external flash, it almost certainly has one or more computers, and all these computers must share information to ensure proper exposure. In addition, if a photo is focused some distance away from the preceding one, the lens needs a discrete period of time to achieve focus. All this is typically accomplished in the “blink of an eye,” but it’s still real time. If you simply compose a picture and mash the shutter button all the way down, there will be a delay before the shutter actually operates, during which time the camera is attempting to focus and determine exposure factors. The subject could move in that time . . .
Second, after the activities initiated when the shutter button was pressed only halfway down have finished and you push the shutter button the remainder of the way down, the camera causes the lens aperture to stop down to the predetermined value, start the shutter movement, and trigger the external flash if scheduled. As the image sensor releases the image, the in-camera processing for JPEG images starts, the image is pushed to the memory card, and then displayed on the LCD monitor for Image Review.
Through Custom Controls, accessible from either the Quick Control screen or the C.Fn2 menu, you can change the function of this button between Metering and AF Start, Metering Start, and AE lLock.
The Depth-of-field Preview Button
The Depth-of-field Preview button is a macro photographer’s delight. In truth, it’s not just macro photographers who should be concerned about depth of field and how to control it. If everything in a picture is in sharp focus, then what do you use to help your audience find the subject you want them to direct their attention to? By opening the aperture a stop or two, you can make the depth of field—that range of depth that is in good focus—shallower, which will generally force the picture components around your subject to appear a bit blurred, or softer. The eye and the brain work together so well in this kind of situation that the soft elements are accepted as supporting the subject, but the subject is allowed to stand out from the background. Rather than gambling on the final result, press the depth-of-field button to preview the final image, looking especially closely at the subject and the competing background. Adjust the aperture to get the desired result.
Figure 3-8. The Depth-of-field Preview Button
Macro photographers are typically chasing the other end of that problem. With the subject so close, depth of field is somewhat shallow anyway. The problem comes from the fact that an SLR camera lens aperture is wide open until the shutter button is pressed. That’s nice because it allows the maximum amount of light the lens can transmit to be used for composition and focusing. But at the same time that’s bad because with the lens aperture wide open, the depth of field is as shallow as the lens can make it. Peering into the throat of a beautiful flower, you would like to have all elements, from the anthers to the ovaries, in focus. At a distance of 10 inches with a lens set at f/2.8, it’s not going to happen. You know that as you stop the aperture down, the depth of field increases, but by how much? That’s where the depth-of-field button justifies its existence: by pressing that button, you stop the lens diaphragm down to your preset value, which allows you to view through the viewfinder the image that will strike the image sensor. The downside to this is that as the lens diaphragm is stopped down, less light is transmitted, which makes it more difficult to see the image. Be aware that the depth-of-field button also works while in Live View.
Through Custom Controls, accessible from either the Quick Control screen or the C.Fn2 menu, you can change the function of this button between Depth-of-field Preview, AF Stop, AE Lock, One Shot & AI Servo toggle, IS Start, Switch to Registered AF Function, One-touch Image Quality Setting, One-touch Image Quality (Hold), FE Lock, VF Electronic Level, Switch to Registered AF Point, AE-Lock (Hold), and OFF.
The Lens Release Button
The Lens Release button allows the removal of the currently mounted lens, either in preparation for mounting a different lens or for mounting the camera’s body cap as you prepare to place the camera back into a carrying bag (many photographers find they have more latitude in placement of body and lenses in the bag if they dismount the lens from the body as they finish their shoot).
Figure 3-9. The Lens Release Button
Pressing the lens release button causes the lens lock pin to be withdrawn from the lens mounting flange, allowing the lens to be rotated in the counterclockwise direction (viewed from the front) for removal. You can ignore the lens release button when you’re mounting a lens. The lens lock pin will be depressed by the lens, but will snap into its locking position as the lens is fully rotated into position.
The Mode Dial Lock Release Button
Most earlier Canon cameras did not provide this Mode Dial lock, and the Mode Dial would occasionally get rotated inadvertently as a result of rubbing against the photographer’s clothing. Now we have a fail-safe mechanism to ensure that the Mode Dial is not accidentally rotated, but at the price of another mechanical procedure that must be considered in the setup for a shoot. Actually, I don’t find it that much of a hassle. I’ve adopted a procedure in which I press the Mode Dial lock release button with my forefinger, and rotate the Mode Dial with my thumb and middle finger. It works with either hand.
Figure 3-10. The Mode Dial Lock Release Button
The INFO. Button
The INFO. button provides access to a significant amount of data, as well as to the built-in electronic level. In shooting mode, there are four states of display for the INFO. button, and successive presses of the button cause the “next” display to be shown. One display is of the major camera settings, a second display provides the built-in electronic level, the third display shows the shooting functions, and the fourth is a blank screen.
In playback mode, the INFO. button also has four different states. One state superimposes nothing on the displayed image, another state displays a minimum of exposure-related information superimposed on the image, a third state reduces the image to a quarter of the screen and adds a brightness histogram to a quarter of the screen, with the remainder of the area showing a great deal of the exposure data for the image. The fourth state replaces data shown in the lower-right quadrant with the brightness histogram, which is replaced with the RGB histogram.
Figure 3-12. The INFO. Button’s Four States While in Playback Mode
The Setting (SET) Button
The SET button is often the last button pressed when setting variables in menu options, and elsewhere. Generally, the camera will recognize the Main Dial and the Quick Control Dial as the tools for selecting menus, options, and variables, but a variable’s value is not committed until the SET button is pressed.
Some menus, and even some other applications, are so convoluted that the Multi-controller is required as well, but the Multi-controller’s button is often disabled, requiring that the SET button be used. In a few instances, you may find yet other buttons being used in ways beyond their defined role in order to accomplish all that a menu needs. Read each screen carefully before you commit an action to ensure that you use the buttons expected by the application.
The Quick Control screen, activated by pressing the Quick Control button, is a unique case. The Multi-controller’s joystick is required to navigate the screen to a specific selection, but the SET button (not the Multi-controller’s button) must be used to open the selected option. The Main Dial and the Quick Control Dial can be used to change option values either in the Quick Control screen or in the option-specific screen opened by pressing the SET button on the selected option in the Quick Control screen.
Through Custom Controls, accessible from either the Quick Control screen or the C.Fn2 menu, you can change the function of this button between OFF, Image Quality, Picture Style, Menu, Image Replay, Magnify/Reduce, and ISO Speed.
The AF Point Selection Button
The AF Point Selection button supports two related functions. When you press this button, then press the AF area selection mode multi-function button (the button with the M-Fn marking), you can select one of six different AF point patterns. A different one is displayed each time you press the M-Fn button. Once you’ve selected the AF point pattern that fits your needs, you press the AF point selection button to display the selectable AF points available for that AF point pattern. Within the range of points allowed by that pattern, you can then use the Multi-controller to navigate to the desired AF point to be used in focusing.
Figure 3-14. The AF Point Selection Button
The AE Lock Button
The AE Lock button (the button below the asterisk icon) provides a means of locking in the exposure parameters you want before you move the point of focus somewhere else. The sequence is to compose your picture, move the camera so that the focus point is on the part of the scene that you want to use to meter exposure, press and release the AE Lock button to lock the exposure parameters, recompose your picture with the focus point in the correct position again, then press the shutter button. If you wish to take multiple photos with the original locked exposure values, simply continue to hold the AE Lock button down while you recompose, focus, and shoot subsequent exposures.
Figure 3-15. The AE Lock Button
Through Custom Controls, accessible from either the Quick Control screen or the C.Fn2 menu, you can change the function of this button between Metering and AF Start, AE Lock, AF Stop, FE Lock, AE-Lock (Hold), and OFF.
The AF Start Button
The AF Start button sits just below the AF-ON icon on the camera. Its role is to provide an alternative to pressing the shutter button halfway for starting the autofocus operation. This is the function that enables what many people refer to as “back button focusing.”
Figure 3-16. The AF Start Button
Through Custom Controls, accessible from either the Quick Control screen or the C.Fn2 menu, you can change the function of this button between Metering and AF Start, AE Lock, AF Stop, FE Lock, AE-Lock (Hold), and OFF.
The AF Mode Selection / Drive Mode Selection Button
The AF Mode Selection / Drive Mode Selection button is one of the dual-purpose buttons. Within six seconds of pressing this button, you can rotate the Main Dial to select the AF mode, or rotate the Quick Control Dial to select the drive mode.
Figure 3-17. The AF Mode Selection / Drive Mode Selection Button
Of course, both of these options can be set from the Quick Control screen as well.
The ISO Speed Selection / Flash Exposure Compensation Button
The ISO Speed Selection / Flash Exposure Compensation button is another of the dual-purpose buttons. Within six seconds of pressing this button, you can rotate the Main Dial to select an ISO speed value or set the ISO Speed to AUTO, or you can rotate the Quick Control Dial to change the flash exposure compensation value. Note that if flash exposure compensation is set on a Speedlite being used with this camera, the camera’s setting will be ignored.
Figure 3-18. The ISO Speed Selection / Flash Exposure Compensation Button
Again, both of these options can be set from the Quick Control screen as well.
The Metering Mode Selection / White Balance Selection Button
The Metering Mode Selection / White Balance Selection button is the third (and last) of the dual-purpose buttons on the EOS 5D Mk III. This is another six-second button: within six seconds of pressing this button, you can rotate the Main Dial to change the metering mode, or rotate the Quick Control Dial to change the white balance selection.
As with the preceding two buttons, both of these options can be set from the Quick Control screen.
Figure 3-19. The Metering Mode Selection / White Balance Selection Button
The AF Area Selection Mode / Multi-Function Button
This button allows you to choose one of six possible autofocus areas, each of the six defining an area dimension that can be repositioned within the 61-point AF frame. But before you attempt to select an area, you must first press the AF point selection button. With the AF area selection mode active, you can now use the Multi-controller’s joystick to position the AF area where you want it.
Figure 3-20. The AF Area Selection Mode / Mutli-Function Button
Through Custom Controls, accessible from either the Quick Control screen or the C.Fn2 menu, you can change the function of this button between FE Lock, AE Lock, One-touch Image Quality, One-touch Image Quality (Hold) VF Electronic Level, and AE-Lock (Hold).
The Creative Photo / Comparative Playback / Direct Printing Button
The Creative Photo / Comparative Playback / Direct Printing button could be considered a “triple purpose” button, but it assumes a “purpose” based on the state the camera is in at the time the button is pressed.
Figure 3-21. The Creative Photo / Comparative Playback / Direct Printing Button
If you attach a PictBridge-capable printer to the camera’s A/V OUT/DIGITAL port and power the printer on, you can press the playback button to access images on the memory card, set up the appropriate printing parameters, and print a picture. Then you can select additional pictures (one at a time) and print them simply by pressing this button, which starts the direct printing function.
If you do not have a PictBridge printer attached but are in playback mode, then pressing this button starts the comparative playback function. With this function, you can view two recorded images side-by-side on the LCD monitor.
The most common reason for pressing this button is to open the creative photo functions that allow you to set up some interesting features for images you are preparing to capture. In normal shooting mode, pressing this button gives you access to a broad spectrum of Picture Styles, a multiple exposure capability, and HDR Mode. In Picture Styles you will find seven predefined styles and three available for customizing to your own needs. Each of the ten can be modified in terms of Sharpness, Contrast, Saturation, and Color Tone, except for the Monochrome style, which replaces Saturation and Color Tone with Filter Effect and Toning Effect. Selecting the multiple exposure capability will allow you to merge as few as two or as many as nine exposures into a single image. The camera provides several options for better optimization of the final image. The feature most attractive to me, at the moment, is HDR Mode. There are a number of reasonably inexpensive software packages that do a comprehensive job of taking a number of images that differ only in exposure and merging them into a single image to yield a broader dynamic range, and they can do some interesting things with toning. But now, you have a subset of those abilities built right into your camera. The EOS 5D Mk III is able to take three images, the exposures of which vary by an amount set by you, merge them into a single image, and even apply a limited amount of toning. I’ve been quite pleased with the results, and encourage you to see if HDR won’t perk up some of your images.
The Rate Button
The RATE button can be used during image playback to assign a subjective rating to any picture or movie, using a scale of one star through five stars. Each time you press the RATE button, an additional star is added, except when there are already five stars allocated, in which case the count of stars is reset to zero. After you press the RATE button, a brief (four second) window will appear on-screen to display the number of stars now allocated to the current image or movie.
Personally, considering the small screen available for assessing the quality of an image as well as the limited user interface, I prefer to wait until I import the images into my computer and do my image-rating in something like Adobe Bridge, where I can see several images at one time. There, assigning a rating consists entirely of selecting the image, then pressing Ctrl plus a number key with a value of 0 through 5. In my world, that’s more efficient and less error-prone than having to press the RATE button as many as five times just to assign five stars to one image.
The Playback Button
This button is used to access and display the images currently on the memory card(s). If you have only a single memory card in the camera, then there’s no opportunity for confusion. However, it’s important that you know what you’re looking at if you have both a CF memory card and an SD memory card in the camera, and that will depend on how you have set up the Record func+card / folder sel. option in the SET UP1 menu. Once you’ve started the playback, be sure that the screen displays some kind of data with the image (three of the four possible display formats, available by pressing the INFO. button, do show this information). Check the upper-right corner of the Playback screen for either a white-borded square with the digit 1 inside (indicating that the CF memory card is being read) or a white-bordered rectangle (in portrait mode) with the digit 2 inside (indicating that the SD memory card is being read). If you want to select the other card, use the Record func+card / folder sel. option in the SET UP1 menu or the Rec function / card selection option on the Quick Control screen.
Figure 3-23. The Playback Button
The Erase Button
As its name implies, this button is the means to deleteing a selected image from the selected folder on the selected memory card.
In playback, locate the image you wish to delete, and press the erase button. At the bottom of the screen, use the Quick Control Dial to select the Erase option, then press SET. The image is now gone. There is no Windows-like recycle bin; there is no way to recover an erased image. If you have Image Quality set up to record both a RAW file and a JPEG file, remember that both files have the same filename but different filename extensions: when you choose either file name for erasure, both files will be erased.
If there are multiple files to be deleted, use the Erase Images option on the PLAY1 menu.
Here, again, I choose not to use the camera’s built-in functions, but wait until I transfer the images to my computer. I find it much faster, and I’m less likely to introduce a problem. I guess I don’t multitask as well as I think I used to. When I go out to take pictures, I want to focus on that, not the “back end” tasks associated with physical maneuvering among images.
The CF Card Ejection Button
The CF Card Ejection button is another device that has no direct effect on the captured image. But efforts to remove the CF memory card from the camera without pressing this button first are doomed to fail or do significant damage to the memory card. (The SD memory card uses an entirely different cardretention system that does not require a button to assist in memory card removal.) Note that when inserting the CF memory card, the ejection button pops out to be accessible for memory card removal.
Figure 3-25. The CF Card Ejection Button
The START/STOP Button
Indicated by the green arrow in the figure, this button serves two specific functions in the EOS 5D Mk III: shooting in Live View mode and shooting in movie mode. The button is a toggle, which means that each press of the button causes the state of the switch to change from Stop to Start or from Start to Stop.
Figure 3-26. The START/STOP Button
With the Live View shooting / movie shooting switch (indicated by the red arrow) set to the movie camera icon, this button is used to start or stop the recording of the movie. With the switch set to Live View, pressing the START/STOP button causes the mirror to flip up out of the light path, with the candidate image now displayed on the LCD monitor.
The LCD Panel Illumination Button
Pressing the LCD Panel Illumination button will turn on the backlighting for the LCD panel, and the backlighting will self-extinguish after six seconds. If you need to turn off the light before it self-extinguishes, you can press the button again. If the Mode Dial is set to Bulb, the backlight will immediately turn off when the shutter button is completely pressed.
Figure 3-27. The LCD Panel Illumination Button
The Joystick
The Joystick is properly named the Multi-controller, but its human-interface is like a joystick. Unlike some game joysticks, this one recognizes only eight points around a circle, but that’s plenty for its functions. The Multi-controller is quite useful for controlling the movement of the active screen component in selecting a focus point, selecting characters from a virtual keyboard when creating copyright information, navigating the options on the Quick Control display, and other tasks. While the Main Dial or the Quick Control Dial will generally provide those same services, the rotation of those dials is usually limited to up-and-down or left-and-right motion. The ability of the joystick to provide up-and-down and left-and-right motion, as well as diagonal motion, makes the joystick my preferred tool when the camera supports it. Having a “set” button as a part of the joystick is icing on the cake.
The Power Switch
The Power switch is certainly the most critical control on the camera. Though a few actions can be performed without the power switch being in the ON position, there is nothing in the realm of composition, automatic focusing, or automatic exposure that is enabled until that switch is placed in the ON position. As with most DSLR cameras, the EOS 5D Mk III is intended to be a battery-powered portable image capturing device. With the developments in battery technology over the past decade, new lithium-ion batteries simply carry more charge, hold more charge, and can be recharged more times than NiCad batteries, NiMH batteries, and even earlier lithium batteries. Even so, there is only a finite amount of battery service available, and there are numerous devices and even camera features that place their own specific power needs on the battery. Unless you’re going to be away from your camera for only a short period of time, set the power switch to OFF or set the Auto Power Off option on the SET UP2 menu to a small number.
Second only to the computers involved in setting the camera for an image capture, the large LCD monitor on the back of the camera is the biggest user of battery power. Most of us rely on it to give us a brief view of a just-captured image, or quick access to option settings with a press of the Quick Control button, or to use the electronic level available from the INFO. button. We rely on it most of all when we’re shooting in Live View.
Then there are the lenses! Most of the lenses used on this class of camera have image stabilization (which uses a significant amount of battery power), Ultrasonic Motor (USM) focusing (which also uses a significant amount of power, but only when the lens is being focused), and in-lens computers, of course. All that power must come from the camera and its power source, typically the battery (or batteries if you’re using the BG-E11 battery grip).
I often find myself in the position of needing to have prolonged access to the camera and its functions, especially menus, in situations such as researching the camera as I write this book. For that, I’ve been able to justify buying the Canon ACK-E6 AC Adapter Kit. This kit allows me to remove the battery and replace it with a battery-shaped adapter that has a long (about 7.5 feet) cable attached to the power-supply brick, which has it own shorter (6 feet) cord that plugs into a typical AC outlet. Now I can set the Auto Power Off option to Disable and not worry about whether I’ll have enough battery to complete some sequence of procedures. Canon encourages the use of the AC adapter for any long activity, certainly for procedures such as sensor cleaning, during which it’s essential that the mirror remain out of the way. Of course, many studio photographers who have little or no need to remove their camera from the tripod use this device.
The Live View Shooting/Movie Shooting Switch
The Live View Shooting / Movie Shooting switch is a simple two-position rotary switch wrapped around the START/STOP button. This switch must be in the movie position (indicated by the red silhouette of a video camera body) in order to set movie-related menus and functions as well as to record a movie. The recording of a movie is initiated by pressing the START/STOP button, and is terminated by pressing the START/STOP button again.
Figure 3-30. The Live View Shooting / Movie Shooting Switch
When the switch is in the Live View position, indicated by the white silhouette of a camera body, you will have the opportunity to use that million-dot, 3.2-inch LCD monitor for composing your photo. As with normal still-photo work, you press the shutter button to capture the image.
The Multi-function Lock
The Multi-function Lock is a form of insurance. Too many photographers have lost good pictures because a dial was inadvertently turned to the wrong position.
Figure 3-31. The Multi-function Lock Switch
You can use the Multi-function Lock option on the C.Fn2 menu to determine which controls you would like to be able to lock. Then with the lock switch moved to the right, the selected controls (the Main Dial, the Quick Control Dial, and/or the Multi-controller) will be disabled for functions that do not require pressing another button before using the selected control. That is, if the Main Dial was selected in the menu and the lock switch was moved to the right, the Main Dial would not be usable for changing the aperture while the Mode Dial is in the Av mode, or for changing the shutter speed while in Tv mode. However, when you press another button such as the Quick Control button first, the Main Dial is available for selecting parameters, just as it normally is.