A new teardown of the OnePlus 15 has answered the question as to what camera hardware is beneath that atypical-looking starbay, and it’s not good news for fans of smartphone photography.
But while a headline-grabbing battery upgrade and better cooling are present, the disassembly reveals that smaller rear camera sensors (with narrower apertures) now feature compared with last year’s model — so it looks a step back on paper.

Teardown Confirms Smaller Sensors Across Modules
The intricate teardown, carried out by Chinese reviewer WekiHome and widely shared in enthusiast communities, notes wholesale sensor swaps within the main, ultrawide and periscope modules. The OnePlus 15 swaps the primary camera from a 1/1.4-inch-class sensor to a smaller 1/1.56-inch model. That adds up to about a 20% decrease in light-gathering area, no small margin when you’re talking low-light capabilities and dynamic range potential.
The spread is more dramatic with the periscope telephoto. Handling the imaging this time around is a 1/2.75-inch sensor—less than half the area of the previous 1/1.95-inch-class hardware. Telephoto modules are already challenged by light and stabilization, so a smaller sensor further means more dependence on aggressive noise reduction and computational reconstruction at higher zoom ratios.
The ultrawide also takes a sensor-size downgrade from the previous generation. While rear system megapixel counts stay at 50MP, it’s the silicon, not so much the headline number, which now plays a bigger role in per-pixel signal quality.
Aperture Changes and Their Low-Light Performance Impact
Beyond sensor size, the lens apertures have been reduced. The main lens changes from f/1.6 to f/1.8. That amounts to roughly a 26% reduction in light at the same shutter speed and ISO. In low-light scenes, the camera needs to decide between slower shutter speeds (introducing blur), higher ISO (which injects noise) or more aggressive computational brightening (which can smear fine detail).
Its periscope lens slows down, going from f/2.6 to f/2.8, a relatively small shift but not great for low-light zoom and indoor performance.
In conjunction with the smaller sensor area, handheld telephoto shots in difficult light will no doubt rely heavily on image stacking and multi-frame processing.

Why The Camera Specs Appear To Go Backward
The remainder of the teardown offers some hints. In its design, OnePlus appears to have prioritized endurance and sustained performance: a larger 7,300mAh dual-cell lithium-carbon battery takes up more internal real estate compared to last year’s 6,000mAh pack, and the vapour chamber now extends to around 5,700 sq. mm from about 4,700 sq. mm — more than a 21% increase. Larger batteries and larger cooling systems push against camera module height and footprint — especially for big-sensor periscope arrangements.
Manufacturers often juggle these constraints. The industry has already witnessed companies switching between camera-first designs and all-day stamina strategies depending on product cycle and component availability. The OnePlus 15 seems more designed toward endurance (not just in the battery sense) and keeping a cooling capacity rather than out-and-out camera silicon.
Other Hardware Changes Revealed In The Teardown
There are genuine bright spots. While the top speaker isn’t taller per se (it’s still fairly low, in fact), it is wider and more symmetrical, which should contribute to stronger stereo separation and a fuller soundstage. The cooling upgrade should also keep performance at its peak whilst gaming and shooting 4K for an extended duration by reducing the amount of thermal throttling over long sessions.
On the other hand, the phone now has three microphones instead of four. WekiHome observes the mic ports are more elongated to differentiate them from the pinhole of the SIM tray — an ergonomic modification if not a necessary functional one. The front camera hardware seems to be the same class and aperture, so expect selfie quality to be much along the lines of the previous generation.
What These Changes Mean For Potential OnePlus 15 Buyers
Specs are not the whole story — there’s this modern thing called computational photography that can help hide hardware compromises in good light and most scenes. Still, physics sets the baseline. The smaller the sensor, and the slower the lens aperture, usually translate to noisier images, a more limited dynamic range and less reliable low-light results (particularly at longer focal lengths).
If what’s most important to you is all-day battery life, thermal consistency and loud, balanced speakers, then OnePlus 15’s design decisions are the right ones for you. If you’re a camera-first buyer who does a lot of night shooting, or uses telephoto zoom frequently, the teardown evidence indicates that last year’s model may still be the rawer deal. Testing from labs and reviewers will, as always, let us know to a great extent how much software tuning can narrow the gap.
For now, the verdict is clear: the OnePlus 15’s internals confirm a bona fide, quantifiable camera hardware downgrade despite pushing harder elsewhere on endurance and sustained performance.