Some Apple Watch Ultra users complain that the watch's display is difficult to see in low light. What is the source of the complaint, which is also voiced in the Apple Support forums?

According to some users, the Apple Watch Ultra display is difficult to read in low light conditions. Although there is no official statement from Apple, it is thought that the watchOS 10 update released last month disrupted the watch's ambient light sensor.

There are also many complaints on Apple Support forums that the information on the Apple Watch Ultra screen cannot be read in the dark. The watch's ambient light sensor cannot calibrate the brightness to a sufficient level.

Watch Ultra 2 users attribute this to the hardware, but owners of the first-generation Apple Watch Ultra have the same complaint. Users report that the problem is particularly noticeable when moving quickly from a brightly lit room to a dark area, and when the Wayfinder and Ultra Modular watch faces are set to night mode. The readability issue persists despite manually adjusting the brightness level in the watch's Settings. The problem is said to be after the watchOS 10.0.1 and watchOS 10.0.2 update.

The screen of Apple Watch Ultra 2, which was introduced with the iPhone 15 series, can be up to 3000 nits brightness. Apple says the Watch Ultra is the model with the brightest display ever. Screen brightness can drop to 1 nit in some conditions.