The Galaxy A54, equipped with the Samsung GN5 sensor, is designed to offer versatile photography at a mid-range price. While the quality in daylight is generally satisfactory, several users notice that night photos show more noise than expected.
The size of the sensor and its ability to capture light in low light
The Samsung GN5 of the Galaxy A54 is a 1/1.56-inch sensor, significantly smaller than that of high-end models. The size of a sensor plays a direct role in the ability to capture light: the smaller the sensor, the fewer photons each pixel receives, which limits sensitivity in low light.
During night shots, dark areas are therefore less illuminated, leading to software amplification to compensate, generating visible digital noise, especially in gradients or uniform areas like the sky.
The aperture and lens play a limited role in noise
The Galaxy A54’s lens has an f/1.8 aperture, allowing for adequate light entry, but insufficient to completely eliminate noise when the brightness is very low. Unlike the larger sensors of the Galaxy S or Ultra ranges, each pixel of the GN5 must amplify the received signal, which enhances digital grain.
Even with extended exposure time, the sensor quickly reaches its limits, and software processing cannot completely mask the artifacts.
Software processing attempts to correct noise but can generate artifacts
Samsung applies software processing to smooth dark areas, improve sharpness, and enhance details. On the Galaxy A54, this process is necessary to compensate for the reduced sensor size, but it has its limits.
In night photos, the algorithm can excessively smooth certain areas, generating a plastic effect or accentuating the remaining pixels, which increases the perception of noise. Tests conducted by DxOMark show that in very dark scenes, software smoothing reduces fine details by 30 to 40%, in favor of less homogeneous noise.
High ISO sensitivity amplifies digital noise
In low light photos, the sensor automatically increases the ISO sensitivity to capture more light. On the GN5, the rise in ISO causes amplification of weak signals but also electronic noise.
On the Galaxy A54, ISOs above 1,600 result in particularly visible grain, especially on uniform textures like walls or the night sky. This amplification is necessary to obtain correct exposure, but it remains a physical limitation of the medium-sized sensor.
Shooting conditions accentuate noise
Noise is more pronounced when:
- The scene is very dark, with few light sources.
- The subject is far from light areas, forcing the sensor to increase gain.
- The shot is handheld, leading to shorter exposure times and thus greater ISO amplification.
In these conditions, even the most efficient noise reduction algorithms cannot produce a completely clean image, explaining user feedback on night shots.
The difference with high-end models
The Galaxy S23 or Ultra have larger sensors and larger pixels, allowing them to capture more light and limit noise. Additionally, the software processing benefits from reference sensors and more powerful processors, offering better management of digital noise and details in low light.
The Galaxy A54, with its GN5, is therefore in an intermediate category: it offers decent performance for a mid-range smartphone, but the sensor’s limitations are clearly apparent at night.
The importance of stabilization and night modes
The Galaxy A54 includes electronic stabilization and night mode to extend exposure time and reduce noise. These modes work well for moderately dark scenes, but they have limits:
- Extended exposure times require a stable support to avoid blur.
- Software noise reduction can smooth fine details.
- In very dark areas, night mode cannot fully compensate for the sensor’s limited sensitivity.
Thus, to obtain a clean image, it is advisable to combine stability and minimal lighting.
Tips for improving night photos
Despite the sensor’s limitations, several techniques can achieve better results:
- Activate night mode to increase exposure time and reduce noise.
- Limit digital zoom, which amplifies noise.
- Photograph near a light source, which allows reducing ISO increase.
- Use a tripod or support, reducing the need for high ISO and motion blur.
These adjustments do not completely eliminate noise, but they allow for sharper and more detailed images in challenging conditions.
