Sony Reveals The Secret Behind Xperia 1 IV's Continuous Zoom Feature

Earlier this month, Sony announced the next generation of Xperia phones - Xperia 1 IV and Xperia 10 IV. Besides the hefty price tag of $1,600, Sony's flagship model also has an extremely interesting feature in the camera system: continuous optical zoom.

Previously, the Japanese company introduced the idea of shifting the lenses inside the camera system on the Xperia 1 III, but this device can only switch between two fixed focal lengths. On the Xperia 1 IV, Sony has finally achieved its true continuous zoom goal: users will be able to switch focal lengths in the 85mm - 125mm range.

This is undeniably a major milestone for mobile photography - and from a purely technological and PR perspective, the feature itself is no small feat. It shows that Sony is not interested in following trends, but looking to prove its point in the smartphone world, and we obviously need to respect the company for that.

According to Sony, the company has been planning to bring continuous zoom to the Xperia lineup for a long time, because it knows this is something customers will be especially interested in. On the Xperia 1 IV, users were able to zoom continuously with extremely high autofocus performance throughout the focal length range of the telephoto lens.

To achieve that, the company had to solve a rather big challenge:

In the conventional optical zoom lens system, depending on the position of the zoom lens (in the case of the Xperia 1 IV)., optical characteristics will vary, such as lens tint, distortion, aberration, etc. Therefore, it is necessary to properly compensate these parameters throughout the focal length range of the zoom lens to get the highest performance.

On the Xperia 1 IV, Sony has done two things: 1) measure the optical characteristics during the production of the camera module, and 2) offset the parameters during the processing of the camera signal. These are relatively complicated procedures that we will not cover in the framework of the article.

Besides the optical zoom, the Xperia 1 IV can continuously zoom from 16mm to 24mm, and up to 375mm during video recording. This also requires a complex manufacturing process. Sony says that it has to use three different lenses, the white point (color temperature) of each lens is calibrated during the production of the camera module, but there can still be slight deviation.

If that happens, the color will change as the lens shifts during inter-lens zoom. To fix, Xperia 1 IV calibrates the white point of 3 cameras at the same time in production to eliminate color deviation. As a result, the device's lenses produce consistent colors and open up the possibility of setting white balance on the Kelvin scale in the Photography Pro and Cinematography Pro apps

Talking about the reasons for choosing the 85mm-125mm focal length range for the continuous optical zoom feature, Sony explains:

On interchangeable-lens (ILC) cameras, the 85mm-125mm focal length is usually used for video recording and photography. portrait. The Xperia's strength is its ability to fine-tune its autofocus on people and animals, and it's especially effective in the aforementioned focal range. With this focal range, mobile users have more flexibility in portrait and pet photography.

As for how the continuous optical zoom system works, the company revealed that it used mechanical actuators to shift the zoom lens elements, focusing element, and optical stabilization unit. learn. However, these actuators don't always move, so battery life shouldn't be affected too much. Concerning the issue of long-term damage to mechanical components, as well as the number of zoom-in, zoom-out (or run time) that the Xperia 1 IV's 85mm-125mm camera system can endure Yes, Sony says it does very thorough testing based on its rigorous standards, but does not give specific numbers.