Traditional film cameras usually require you to move the lens, or your whole camera, closer to an object to zoom in on it. This is called optical zoom. Digital cameras, on the other hand, give you the option to zoom digitally. Many digital cameras come with both digital and optical zoom, each of which has its own advantages and disadvantages.
The Difference Between Optical and Digital Zoom on Digital Cameras
How Optical Zoom Works
Optical zoom involves moving your camera lens closer to the object you’re taking a picture of, with millimeter differences in actual closeness corresponding to more dramatic perceived closeness. How you optically zoom depends on the type of digital camera you have. A compact point-and-shoot camera allows you to control optical zoom with a button or lever attached to the body of the camera. If you use a digital single-lens reflex (dSLR) camera, you manually extend or retract the lens.
Limitations of Optical Zoom
Cameras with optical zoom are limited in how far they can zoom. Basic point-and-shoot cameras, for example, may zoom only three times, which is inadequate for taking pictures of objects that are more than a couple dozen feet away. dSLR cameras are more versatile, but if your lens doesn’t have adequate optical zoom to photograph your desired object, the object will look small in size.
How Digital Zoom Works
Digital zoom entails “blowing up” an image to make objects in it look bigger – the camera does this after you take the picture. Basically, you select a small part of the field and then augment its size to that of the original field. Digital zoom permits you to increase the size at which objects appear, no matter how far you were from them when the picture was taken.
Limitations of Digital Zoom
How effect the digital zoom function is depends on the megapixel resolution of your camera (how many dots or pixels it captures per inch). If your camera has a high megapixel resolution, your digital zoom will result in a clear and crisp photograph. If it’s low in resolution, on the other hand, your digital zoom will make this image appear blurry.