Understanding Digital Photography
Digital Zoom Versus Optical Zoom
Many digital cameras offer both digital and optical zoom. These two often confuse the average camera buyer, until you know what you’re looking at.
Optical zoom works much like the zoom lens on a 35 mm film camera. It changes the length of your camera’s lens and draws the subject closer to you. The optical zoom keeps the quality of the picture. Digital zoom works differently. It simply takes the picture and crops it then enlarges the part that is left. It causes the quality of the photo to be reduced, sometimes greatly.
What this means in terms of output is you may have a larger view of an object with the digital zoom, but chances are your image will become unfocused. Details will become lost. It is actually best to turn off the digital zoom feature of your camera if possible. This will prevent you automatically zooming in too close as the digital zoom is often an extension of the optical.