This is the seventh article in a series on "understanding your camera" that I am writing as I teach camera basics and camera operation to my children.

SLR cameras and many point-and-shoot cameras have a mode dial, allowing you to select one of a number of different modes, depending on the conditions and how you want the camera to respond. However, many people do not understand the different modes, and leave their camera in the fully automatic mode all the time.

It is important to understand exposure, and what the camera is doing when you take a photo, and that is the reason why I'm looking at the different modes.



In full auto mode, the camera is making almost all the decisions about the exposure (aperture, shutter speed and ISO), and has to guess what you want. In many situations, you are much better off using some of the other modes available on your camera, as it will allow you to make decisions about some of the variables, while still (optionally) allowing the camera to make decisions about other variables.

In this post, I look at each of the modes available on most cameras, and provide some information about how the camera reacts when configured to use that mode.
(Note that I am more familiar with Canon cameras, so some references are specific to Canon cameras. However, the description of the modes is just as applicable to other brands of cameras.)



In the auto modes, the camera is making almost all of the decisions for you with regards to the exposure.

The auto modes available on many cameras include:

Auto - In full auto mode, all the auto-focus points are enabled, AI servo auto-focus mode is selected, and the camera decides the ISO, shutter speed, aperture, and whether the flash will be used. The only decisions you are making are in relation to where to point the camera, how far to zoom, and when to press the shutter button.

Program - Also known as "Program AE" (auto exposure) mode, this gives you control over some settings, with the shutter speed and aperture being set by the camera, but the AF mode, drive mode, flash and other functions can be adjusted.
When in Program mode, the camera will typically try to use a large aperture, and will select an appropriate shutter speed to provide a useful exposure.

Program Shift - When in Program mode, you can adjust the shutter speed and/or aperture, and the camera will automatically adjust the other to ensure the same exposure is achieved (ie, if you open the aperture by one stop, the camera will halve the shutter speed to reduce it by one stop). This is referred to as "program shift".
To use program shift, half-press the shutter button to get the camera to take an exposure reading. Now rotate the main dial (the one just behind the shutter button), and you will see the aperture and shutter speed in the viewfinder display change as you rotate. Note that the camera will revert back to its default Program mode settings, and will discard the program shift values once you remove your finger from the shutter button, or if you take a photo.
Program shift is not available when using a flash. Note that the exposure lock button can be used to lock the exposure at the shifted values to allow multiple photos to be taken at those exposure settings.



Many cameras have a selection of semi-automatic modes, which tell the camera the general idea of what you want to do. Along with the full-auto mode, Canon refers to the semi-automatic modes as "basic zone" modes. When using these modes, the camera will typically also select a different picture style, ie, more saturation to provide vivid greens and blues for landscape images, etc.

Portrait - Designed for portraits, this mode uses a larger aperture for provide a smaller depth of field. Continuous shooting mode is also enabled, and if the camera decides it is necessary, the built-in flash is used.

Landscape - This mode uses a smaller aperture for larger depth of field, and disables the flash. The smallest aperture depends on the ambient light (and the selected ISO), as the camera will ensure a shutter speed of 1/60 seconds or faster is achieved.

Macro Mode - As the name suggests, this mode is designed for closeups. The camera will select a wide aperture and fast shutter speed to ensure camera shake isn't an issue (the effect of camera shake is amplified at short distances), and will use the built-in flash if necessary.

Sports Mode - Designed for shooting moving subjects, the centre AF point is enabled, continuous shooting is also enabled, and the camera will try to achieve as fast a shutter speed as possible.

Night Portrait Mode - Using a longer shutter speed to capture ambient light from dark background, this mode will typically use a flash to light up a person or object in the foreground. Due to the longer shutter speeds that normally result when using this mode, a tripod is often required.



Creative modes allow you to have some control over some settings, and allows the camera to make decisions on the other factors affecting the exposure.

Aperture Priority (Av, for "aperture value") - You set the aperture with the main dial, while the camera determines an appropriate shutter speed to provide a suitable exposure.
This mode is typically used if you want to control the depth-of-field in the photo, ie, large depth-of-field for landscape photos, or a short depth-of-field for portraits.

Shutter Priority (Tv, for "time value") - Similar to aperture priority, but in this mode, you set the shutter speed with the main dial, while the camera determines an appropriate aperture.
Shutter priority is normally used when a specific shutter speed is required, ie, fast shutter speed to capture moving objects, or a slow shutter speed to capture blurred movement.

A-DEP (automatic depth-of-field) - Designed to maximise depth-of-field, in this mode, the camera will try to keep all foreground and background items covered by focus points in focus by selecting an appropriate aperture.



In manual mode, it is completely up to you to tell the camera what aperture and shutter speed you want it to use.
Note that bulb mode is only available when the camera is in manual mode (bulb mode is a special mode where the shutter remains open for as long as the shutter button is held down, typically with a wired or wireless shutter release, and is normally used for exposures longer than 30 seconds).



The auto modes, and even the semi-auto modes, have limitations, because the camera is making a lot of decisions on your behalf. However, the camera is basing those decisions on a small selection of inputs, while you as photographer are much more aware of the environment, and typically knows what you want to achieve. The creative modes provide you with a lot more flexibility and control over the camera.

The best way to get a better appreciation for the different modes on your camera is to try them out!

If you normally stick to the auto modes (auto and program), then try using some of the semi-auto modes (portrait, landscape, macro, sports, night). Similarly, if you are already familiar with the semi-auto modes, then try using some of the creative modes (aperture priority, shutter priority).

In the next article in this series, I will be looking at the camera modes I use most frequently, as well as the reasons why.