Digital zoom enlarges an image by cropping and resizing pixels. Unlike optical zoom, it does not use the lens to magnify the scene. Instead, it increases the size of the captured image, which can reduce clarity.
In surveillance systems, digital zoom helps focus on specific details during live viewing or playback. For example, an operator may zoom in on a license plate to identify a vehicle.
However, the more you zoom in digitally, the more image quality may drop. Therefore, it works best when paired with high-resolution cameras.
As a result, digital zoom is useful for quick analysis, but optical zoom remains the better choice for clarity.