Your guide to digital camera scene modes
July 3, 2008
With summer travel time upon us, you may find yourself trying to capture the beauty of scenic vistas. Landscape mode helps you take the guesswork out of properly exposing and focusing on the vast scenes before you.
Because of the laws of physics we can focus a lens so that just about everything—from nearby all the way out as far as the eye can see—will turn out sharp. Technically, this is referred to as the Hyperfocal Distance, and the actual specification varies depending on the focal length of the lens and the f-stop that has been selected. If a lens has a Hyperfocal Distance of 30 feet, for example, and we set the focus at 30 feet, everything from one-half that distance (i.e., 15 feet) to infinity will be in focus. Wideangle lenses are said to have greater depth-of-field because their Hyperfocal Distance is closer than telephoto lenses.
The Landscape Mode on a digital camera exploits this phenomenon by zooming the lens to a wideangle setting and small f-stop and then focusing as described above. Most cameras assume that your landscape shots include at least some green scenery, so they boost color saturation and sometimes favor green and blue hues (bad news for those of you who live on the dessert or in Antarctica).
Since the camera chooses a smaller f-stop, that also means it will select a slower shutter speed to compensate for the loss of light. Avoid camera shake by using a tripod, leaning the camera against a tree, car roof or railing--anything that will stabilize the camera.