Samsung and Apple are putting the variable aperture on the wrong camera

Rumors are circulating that Apple and Samsung could bring variable aperture main cameras to their future smartphones. These claims come almost a decade after the Samsung Galaxy S9 series first debuted a dual aperture, allowing the rear camera to switch between two distinct aperture sizes.

Apple and Samsung would join Xiaomi, HONOR, and others in offering phones with variable aperture main cameras in recent years. However, I strongly feel that this technology is a better fit for telephoto lenses than for the main lens. Here’s why.

The vast majority of smartphones have cameras with a fixed aperture. An aperture is the opening that allows light to hit the camera sensor. However, some phones, like the HONOR Magic 7 Pro and Xiaomi 14 Ultra, have main cameras with a variable aperture. This means users can adjust the size of the opening, with varying results.

A wide aperture (e.g., f/1.6) creates a shallow depth of field, keeping the subject in focus while the background is pleasantly blurred. This also enables increased light intake, allowing for brighter, cleaner shots in mixed lighting. Meanwhile, a narrow aperture (e.g., f/4.0) brings more of the entire scene into focus. This is handy if you’re taking photos of landscapes, groups, or want macro shots without too much depth of field.

One-inch primary cameras debuted a few years ago, but these huge camera sensors were initially paired with a wide, fixed aperture. Unfortunately, this combination often resulted in an extremely shallow depth of field and focusing issues. In fact, when I reviewed the vivo X90 Pro, I sometimes found myself taking shots of a subject that wasn’t entirely in focus due to the tiny focus area. Check out these images below.

Thankfully, a variable aperture helps address this issue. Phones like the Xiaomi 14 Ultra paired a variable aperture with a one-inch main camera to great effect. This allowed the main camera to focus on close subjects while offering fine control over depth of field. Xiaomi even uses the variable aperture to create star-shaped light sources in scenes.

Smartphone makers have stalled somewhat in adopting one-inch main cameras. In fact, Samsung, Apple, and Google all use smaller main cameras and aren’t likely to use one-inch sensors for a while. So a variable aperture on the Galaxy S27 Ultra or iPhone 18 Pro main camera would be cool, but it likely wouldn’t be a pressing need. Today’s smaller sensors simply aren’t going to have focusing issues to the same extent as one-inch cameras. On the other hand, a telephoto camera with a variable aperture lens opens up some interesting possibilities.

Colleague Rob Triggs rightfully notes that aperture changes are more pronounced on a telephoto camera compared to a typical 24mm-equivalent main camera. Check out his comparison below, showing 20mm and 70mm shots at various apertures. Note how the bokeh effects in the background look more prominent owing to the closer perspective and natural background compression.

Telephoto cameras are also the go-to for portrait shots as they offer a desirable compression for faces. So the combination of a tele shooter and a variable aperture should make for even better, more aesthetically pleasing portraits. That’s because a tele camera with a wide aperture delivers a naturally shallow and accurate depth-of-field without resorting to heavy-handed, software-based background blur that’s prone to depth errors. A tele camera with a decently sized sensor and a wide aperture can also take pictures that are less flat than zoom cameras with small sensors and narrow apertures.

A telephoto camera with a wide aperture would also be useful in low-light situations, letting in as much light as possible. This doesn’t sound like a huge deal, but secondary cameras tend to struggle in low-light situations compared to the primary camera. The best camera phones already offer telephoto cameras with reasonably wide apertures, but a variable aperture that can go even wider could help narrow the gap with the main camera.

There are also a couple of reasons why you’d want to switch the telephoto camera to a narrow aperture. The first reason is that it allows you to get a little closer to your subject, making this ideal for macro photos. A narrow aperture also means much more of your scene is in focus, and that’s perfect for situations like landscape photos and group shots with the tele lens, where you need uniform sharpness across the picture.

There is one significant challenge standing in the way of telephoto cameras with variable aperture lenses. Telephoto and periscope camera modules are complex and take up a lot of space compared to a main camera module. So adding a complicated variable aperture mechanism to an already complex camera module would be a significant engineering hurdle. The combined bulk also suggests that variable-aperture telephoto cameras would have a significant bump at first.

Nevertheless, we’ve already seen smartphones with variable optical zoom cameras, dual-periscope lenses, 10x cameras, one-inch main cameras, and other crazy photographic innovations. It therefore stands to reason that a variable aperture telephoto camera might not be an insurmountable challenge. My fingers are crossed that Google, Samsung, Xiaomi, and others can clear this hurdle and deliver an unmatched zoom camera experience.