iPhone 15 Pro automatically switches camera lenses — how to disable this?

That iPhone has three cameras:

• 12MP Ultra Wide: 13 mm, ƒ/2.2 aperture
• 48MP Main: 24 mm, ƒ/1.78 aperture, second‑generation sensor‑shift optical image stabilization, which can double as a 12MP Telephoto, 48mm, ƒ/1.78 aperture
• 12MP 3x Telephoto: 77 mm, ƒ/2.8 aperture, optical image stabilization

The Main camera has more light gathering ability (per unit of sensor area) than the 3x Telephoto one does.

(2.8 / 1.78)^2 = 2.474 times as much light gathering ability (per unit of sensor area).

So in dim light it might be reasonable to switch to the Main camera @ ƒ/1.78 and use digital zoom (ugh) rather than sticking with the 3x Telephoto camera and ƒ/2.8.

But the bottom line is that while there are three cameras and three lenses, that's a compromise forced by the small size of a smartphone. In a digital SLR or mirrorless camera, you'd have a large sensor, and mount a large zoom lens or prime lens in front of it, and it wouldn't be the camera choosing among sensors and lenses. Here, three cameras together with software do the job. Sometimes the software might use multiple cameras or might not always use the individual cameras in the way you might prefer. That's life.

Apple has decided the methods by which it will implement its advertised functionality. You are asking for a way to override Apple’s design decisions.

t1mm4te wrote:

Version of IOS is 18.5.

This version is no longer current.

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