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Part four: zoom

When is a zoom not really a zoom? When it's on your mobile device. Why sometimes the simplest solution for getting a good zoom is the best, and why you should avoid digital zoom.


A pixelated image of a man holding a mobile phone

Fast facts

Digital zoom

Digital zoom takes a portion of the image and enlarges it. In other words, the camera crops a portion of the image and then scales it to fill the frame. Subsequently, you lose image quality.  If you’ve been using a digital zoom and wondered why your pictures did not look that great, now you know.

Optical zoom

Optical zoom changes the magnification of images with the actual optical glass before the images reach the imaging sensor. Some modern smartphones now feature optical zoom functions.

Most smartphones have digital zooms. A digital zoom works by essentially focusing on a portion of the image scaling and cropping it to give the impression of zooming, however, a considerable amount of image quality is lost. This can result in pixelation or softness.

It is better to avoid using your smartphone’s digital zoom. If at all possible just get physically as close to the subject as possible. This will enable you to get tight shots and close-ups without sacrificing image quality.

Some more modern smartphones (like the iPhone 7 / 8 Plus, iPhone X and later) have optical zoom functions which will not reduce the quality of your image. Please note that some zoom function lenses may have a smaller aperture that may make filming in low light more challenging.

There are several clip-on lenses available for mobile devices that allow actual zooming without a loss in picture quality.

...if you zoom in too far, it's very possible that the image may not be as sharp as it could be...

Part three: be stable   Part five: lighting