Why Feature Interchangeable Lenses in a Smartphone?

Anyone who has ever used a smartphone with a telephoto camera will be familiar with this issue: the image quality drops significantly compared to the primary camera. The main reason for this is how tiny the sensors behind the telephoto lenses are, and tiny sensors capture very little light.

Physics is to blame for the small sensors. The larger the sensor, the bulkier the lens, and telephoto lenses are generally larger than wide-angle lenses. If you don’t want your smartphone to arrive in a brick form factor, then it is unfortunate but true for this to be possible only with small sensors, and tricks like periscope lenses only help to a limited extent.

Interchangeable Lenses are the Solution

The solution from Realme looks like this: Between the “regular” smartphone cameras on the back of the concept smartphone is a naked image sensor in 1-inch format—Sony’s IMX989. Unlike classic interchangeable lens cameras, the sensor is protected by a layer of glass, so you don’t need a protective cap or anything similar if you do not mount a lens on the phone.

A lens mount ring is attached around the camera island behind, which can be used to attach lenses to the smartphone. Realme relies on the Leica M system here. There is a corresponding button in the camera app to switch to the mounted lens.

And yes, if you have a high-quality telephoto lens attached here, the image quality is remarkable. At MWC, the difference to the telephoto camera shot by an iPhone 16 Pro was definitely jarring. To be fair, anything else but an incredible result would be a bitter disappointment with this gigantic lens.

Concept phone with Leica M lens mount, showcasing two smartphones connected for photography.
The image quality is worlds better than with “normal” smartphone telephoto cameras. Of course, the Realme smartphone with a DSLR lens is also far thicker! / © nextpit

Unfortunately, it remains unknown when Realme will launch the concept smartphone and how much it will cost.

What is Xiaomi Planning?

At its MWC press conference, Xiaomi also announced a smartphone with interchangeable lenses known as the Xiaomi 15 Concept. However, unlike Realme, Xiaomi is not relying on an existing lens system, but on integrated sensor lens modules that can be docked onto the smartphone. The principle is reminiscent of Sony’s QX10 or QX100 or Ricoh’s GXR system.