The sensor quality plays a pivotal role in determining the low-light noise performance of smartphone cameras, and this is clearly evident when comparing the Samsung Galaxy S25 Ultra with its predecessors and competitors. Despite Samsung’s efforts to enhance camera capabilities, the S25 Ultra exhibits a nuanced performance in low-light conditions that is influenced by both its sensor hardware and software processing.
The Samsung Galaxy S25 Ultra retains much of the camera hardware architecture from the S24 Ultra, including the flagship 200MP main sensor, supplemented by a 50MP ultra-wide and telephoto sensors. However, the core sensor technology itself has not undergone radical changes, which partly explains why the low-light noise characteristics have not dramatically improved and, in some cases, have regressed slightly compared to the S24 Ultra[1].
Sensor Hardware and Low-Light Noise
One of the critical points raised by users and experts is that Samsung’s own sensors, such as those used in the S25 Ultra, tend to be less effective in low-light scenarios compared to Sony sensors found in some competing devices. This inferiority manifests as more noticeable noise, color inaccuracies (such as yellowish or greenish tints), and reduced clarity in dim environments[3]. The sensor’s ability to capture light efficiently and its pixel design directly affect the noise level; Samsung’s sensors, while high resolution, sometimes struggle with noise control when lighting is poor.
In practical terms, this means that in low-light photography, the S25 Ultra can produce images with more intrusive noise and chromatic aberrations, especially in high-contrast scenes or strong backlighting, compared to older models like the S24 Ultra[1]. This is despite the S25 Ultra’s generally good texture retention and detail preservation in many lighting conditions.
Software Enhancements and Noise Reduction
Samsung has introduced software-based improvements to mitigate sensor limitations. The S25 Ultra employs a new Spatio-Temporal Filter and an advanced Nightography mode that leverages AI to differentiate moving and static objects in low light, aiming to reduce noise without overly softening details. This software approach helps improve video noise reduction in real time, making low-light video recordings cleaner than before, although some softness remains due to aggressive noise suppression[2].
Despite these enhancements, reviewers note that noise reduction on the S25 Ultra can sometimes be unstable across consecutive shots and may introduce artificial sharpening or color casts in night mode, which contrasts with the more balanced but noisier output in standard low-light shooting[1]. The balance between noise reduction and detail preservation remains a challenge.
Comparison with Older Models
Compared to older models like the S24 Ultra, the S25 Ultra shows a mixed bag in low-light noise performance. While it sometimes preserves better detail in very low light, it generally exhibits more visible noise and chromatic noise artifacts. The S24 Ultra, with slightly different sensor tuning and noise processing, often delivers cleaner images in similar conditions[1][2].
In summary, the sensor quality of the Samsung Galaxy S25 Ultra impacts low-light noise by limiting the hardware’s inherent light sensitivity and noise control, which Samsung attempts to compensate for with sophisticated software algorithms. However, these software fixes cannot fully overcome the physical limitations of the sensor, resulting in a low-light noise profile that is sometimes more intrusive than on older models. Users seeking the best low-light noise performance might notice that the S25 Ultra’s sensor and processing pipeline still lag behind some competitors using Sony sensors or alternative hardware approaches.
This analysis underscores the importance of both sensor hardware advancements and software innovation in achieving superior low-light photography in flagship smartphones.
[1] https://www.dxomark.com/samsung-galaxy-s25-ultra-camera-test-retested/
[2] https://petapixel.com/2025/01/29/samsung-s25-ultra-review-it-smooths-out-the-rough-edges/
[3] https://eu.community.samsung.com/t5/galaxy-s25-series/s25-camera-sensors-are-bad-for-low-light/td-p/11881207