Digital zoom

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Digital zoom its a method of increasing the apparent focal length at which a photographic or video image was produced. Digital zoom is accomplished by cropping an image down to a centered area with the same aspect ratio as the original, and usually also interpolating the result back up to the pixel dimensions of the original. It is accomplished electronically, without any adjustment of the camera's optics, and no optical resolution is gained in the process.

Because interpolation disturbs the original pixel layout of the image, as captured by the camera's digital sensor, it is usually considered detrimental to image quality. The results of digital zoom are, however, sometimes superior to the results of manual cropping and resizing (interpolation) in post-production. This is because the camera may apply its interpolation before performing lossy image compression, thereby preserving small details that would otherwise be lost. For cameras that save images in a raw format, however, and resizing in post-production will yield results superior to digital zoom.

Some digital cameras rely entirely on digital zoom, lacking a real zoom lens. Other cameras do have a real zoom lens, but apply digital zoom automatically once its longest focal length has been reached. Professional cameras generally do not feature digital zoom.