Optical zoom changes the lens’s field of view using the lens optics. Digital zoom enlarges or crops the image captured by the sensor. Sony explains that its digital zoom modes can reduce image quality compared with optical zoom, although the exact behaviour depends on the camera and zoom feature. www.sony.com

This distinction matters when you zoom during a recording and want to know whether the camera is using the lens or processing the image.

What optical zoom does

With optical zoom, the lens changes its focal length to make the subject appear closer or farther away in the frame. If your camera has an optical zoom lens, you can usually move through its supported range without the camera simply enlarging a smaller crop.

Optical zoom has limits: once you reach the lens’s longest focal length, the camera may offer digital zoom or another form of image enlargement.

What digital zoom does

Digital zoom enlarges part of the sensor image. Depending on the camera, it may crop the image, interpolate pixels or use a processing method designed to preserve more detail. The result varies by device and setting.

Before relying on digital zoom, test it at the resolution and delivery format you intend to use. Check fine details and edges on a larger screen. If the result looks soft or blocky, move closer, use optical zoom or reframe during editing if the original footage has enough resolution.

For more about how sensor size affects framing, see RouteNote’s guide to camera crop factor. Then browse RouteNote Licensing for music and sound effects to match your footage.