What's the difference between digital and optical zoom?

Digital zoom. Wide-angle lens. Megapixels. Pixel binning. Computational photography. There’s a lot of jargon when people (expert or not) talk about the technology behind modern photography.

With smartphones in particular, some of the most common terms you’ll hear are “digital zoom” and “optical zoom” – but what do they mean? 

Optical zoom is actually a change in the mechanics of the lens you’re using, specifically in phone cameras, the sensor – which is what captures light. Digital zoom is magnification technology within the phone (or camera). Because of this, digital zoom (which is somewhat like cropping) can affect the integrity of the picture and cause pixilation. 

Some phones use more advanced digital zoom technologies that use AI to interpolate (interpret, replace and likely smooth) the information missing in the digital zoomed photo that caused the pixilation. This doesn’t necessarily remove all the loss in the quality of the image, but should make it less obvious to the average camera phone user. This is usually called “hybrid optical”. 

For example, the Samsung Galaxy S22 series uses a mix of physical changes to their lenses and changes to their technology to improve the quality of their photography, which allow the phones to process more data than previous S series phones. The ability to process more data allows them to use that data differently in their algorithms. While Samsung does use multi-frame processing to blend multiple images to build detail and light, they looked for ways to identify objects to capture the true shape in low-light conditions , and then finessed that in portrait mode by zoning in on the small details. They’ve brought this technology into their zoom as well, using what they call Adaptive Pixel technology to bring out the details and colours of a scene.   

The Pixel 6 and Pixel 6 Pro phones use technology they call “Super Res Zoom” which they’ve used since the Pixel 3 phones. Super Res Zoom at its most basic level merges multiple photos together rather than just using the digital zoom on a single image. The Pixel 6 phones also use machine learning and AI functions with their Tensor chip including motion detection algorithms, laser detect auto focus system and digital bracketing to do everything they can to make the photo on your phone to look like what you see in real life. 

OPPO’s Find X3 Pro has a 2x optical zoom and up to 20x digital zoom, and has approached the camera system a bit differently than the rest, with the main and ultrawide cameras using the same sensor, and thus having 2 primary cameras. This seems to be how they intend to manage digital zoom, with some mixed results, particularly for the digital zoom 5x and beyond, according to multiple reviewers.  

As technology improves, the quality of digital zooms will (hopefully) only improve from here, so get snapping. Check out the latest phones (and phone cameras) we have at Optus today.