Camera Operation

Digital cameras have three basic modes: Off, Capture, and Preview. Capture is the mode you use when the camera is ready to record an image. Preview is when you're looking at your previously shot images on the LCD screen.

Capture Mode
In Capture mode, the camera is ready to capture an image. On most digital cameras (except for many SLR types), there is a preview of what you're about to capture displayed on the LCD screen. It is important to understand that the process of capturing an image involves a few sophisticated processes most of which will be done automatically by the camera, but all of which you must initiate by first pushing the exposure button HALF WAY down.

When you push the exposure button half way down, you ask the camera to analyze you scene and make adjustments, such as auto exposure, auto focus, and auto white balance.

  • Exposure:  The camera must make settings of its own to accomodate the amount of light that is in your scene.  It must judge the amount of light and set its shutter speed and aperture accordingly.  When this is done automatically, it is referred to as "Auto Exposure".
  • Auto Focus: Modern cameras have the amazing ability to focus automatically, which can free you to make more sophisticated decisions like composition, etc.  This process isn't magic, however, but involves having the camera sense the greatest amount of contrast at the edges of your subject. (more on this later) This means that it can sometimes fail to work on subjects that have indescernable details.
  • Auto White Balance:  We'll talk more about this later, but basically this means that the camera will automatically sense how best to configure the colors in your scene to make the best image.  Again, all of these automatic settings are prone to failure and a function of this class will be to best control/override them to get the best image.

Preparing to Shoot

I have found that the best approach is to push the button halfway down first (to prepare the camera to shoot), then push it the rest of the way at the instant that you want to create a photograph.  If you just simply push it down all the way in one step, you will likely experience a slight or pronounced delay or hesitation that is the result of the camera performing the above operations.  This delay can be frustrating if you are trying to capture quick action.

! If the camera will not fire, it may because one of these above operations could not be performed, or had problems:

  • Your camera may not be able to focus if your subject is too dark or too undifferentiated.
  • Your camera may not be able to determine correct exposure if it is too dark.


Preview Mode
Preview mode allows you to look at the images you just shot, and can be a great tool to judge your photographic decisions before it's too late to make adjustments. Generally when you're in preview mode, you can use a set of buttons to shuffle through your images (forward, backward). You can also generally use the zoom control to allow you to inspect the images up close, or let you zoom out and see a set of thumbnails from which to choose. You can also delete images that you don't want to keep.