Variable aperture brings iPhone 18 Pro closer to professional cameras

The biggest camera upgrade on this year’s iPhone 18 Pro and iPhone 18 Pro Max involves a hardware feature long familiar to professional photographers: a physical aperture that can be adjusted.

Variable-aperture technology allows the iPhone 18 Pro to control how much light enters the lens. It represents a significant step forward, not only improving low-light photography but also giving users greater control over depth of field.

When the aperture opens wider, more light reaches the sensor, allowing the camera to capture more detail and color in dark environments.

A wider aperture also produces a shallower depth of field, helping subjects stand out from the background and creating more natural background blur, particularly for portraits.

Conversely, narrowing the aperture increases depth of field. This allows more areas of the frame to remain in focus at the same time, making it suitable for landscapes or situations where users want the entire scene to appear sharp.

According to Apple, the iPhone 18 Pro can automatically adjust the aperture according to shooting conditions.

Apple is also expected to allow users to control the aperture manually through the Camera app.

The change is notable, although variable-aperture technology itself is not entirely new to smartphones.

Samsung previously equipped the Galaxy S9 and Galaxy S10 with a dual-aperture system that allowed the camera to mechanically switch between f/1.5 and f/2.4. The feature was dropped starting with the Galaxy S20 series.

Huawei and Xiaomi, meanwhile, have continued using variable-aperture cameras on some premium smartphones. The Xiaomi 14 Ultra, for example, supports an aperture range from f/1.63 to f/4.0.

Apple’s adoption of the technology, however, could make a significant difference through the integration of camera hardware, computational photography and its broader software ecosystem.

iPhone 18 Pro can authenticate original photos in the AI era

Alongside the camera hardware upgrades, Apple has introduced an entirely new feature called Reference Image on the iPhone 18 Pro.

The technology is designed to authenticate the origin of a photograph, allowing viewers to determine whether an image captured on an iPhone has subsequently been altered using AI.

As synthetic images and AI-generated content become increasingly difficult to distinguish from real photographs, this could become one of the iPhone 18 Pro’s most significant new features.

Reference Image essentially creates a digital authentication record for a photograph immediately after it is taken.

If the photo is later modified using AI, users can access the original as a “digital negative” and compare it with the altered version.

The technology is designed to address an increasingly important problem on the internet: determining whether an image accurately represents what a camera captured or has been manipulated by AI.

Apple is expected to use Private Cloud Compute to process some information associated with photographs taken using the iPhone 18 Pro camera.

The system then generates a cryptographic signature that serves as a form of authentication for the original image.

Importantly, the authentication record is not limited to the iPhone on which the photo was taken.

Users can share signed images with others while retaining authentication information that can later be used to verify their origin.

The technology could offer a new approach to image verification in the AI era, particularly as manipulated content created with generative tools becomes increasingly widespread.

Reference Image, however, will have geographic limitations. According to currently available information, the feature will not be offered in the European Union or China.

Apple is also developing ways to identify images generated or edited using its own AI tools.

Image-generation features such as Image Playground and new Apple Intelligence editing tools, including Extend and Spatial Reframe, will add a SynthID marker to generated images.

The move suggests Apple is seeking to establish a clearer distinction between photographs captured by a camera and content generated or modified using AI.

While Reference Image is intended to establish that an image originated from a camera and has not been manipulated, SynthID serves to identify images involving AI.

With the iPhone 18 Pro, Apple is therefore doing more than improving photography. It is also positioning the camera to address a much broader challenge: establishing the authenticity of images in the AI era.

The combination of a variable aperture, greater control over light and image-authentication technology could set the iPhone 18 Pro apart not only in image quality, but also in how users trust and share digital content.

Hai Phong