Learn how smartphone cameras capture and process photos taken at night or in dark places, preserving detail and reducing noise
OR night mode it is a function present in cell phone cameras to improve the quality of photos taken in dark environments. This is done with the adjustments of parameters such as exposure time and ISO. The goal is to increase image sharpness in low light conditions.
The feature is adopted by brands such as Apple, Google (Pixel line), Motorola, Samsung and Xiaomi, but under different names. On iPhone, the naming is Night mode; on Motorola smartphones, it is night visionFor example.
Index
How does scene detection for night mode work?
On most cell phones, night mode is automatic, although it can be activated manually.
The camera application uses artificial intelligence to perform scene detection, i.e. to evaluate the ambient lighting conditions. If this process indicates that the environment is dark, night mode is activated.
The analysis is based on the level of light entering through the camera lens and reaching the image sensor. Other factors are often considered. The mobile can use the ToF sensor to calculate the distance to the subject (what will be photographed). You can also analyze the movement that the user makes with the smartphone.
Based on the data obtained from scene detection, Night Mode adjusts parameters such as shutter speed, lens aperture, exposure and ISO so that the photo can be recorded with sharpness and focus on the subject.
Why does the camera take time to shoot in night mode?
Shooting time is usually longer in night mode, especially when there is no optical stabilization. This is because the camera increases the exposure time to capture more light. At the same time, the ISO value is carefully adjusted to avoid excessive image noise.
Also, night mode can combine multiple images into one to increase the level of detail. It’s an approach reminiscent of applying HDR, combining several exposures of the same image to generate a photo with greater dynamic range.
How does pixel binning improve night mode photos?
Some advanced cell phones use pixel binning to improve the quality of night photos. This is a technique that combines pixels to form a larger pixel (or superpixel).
Pixel binning is useful in night mode because the grouping of pixels makes the final image brighter. The more pixels you combine, the better. See the case of the Galaxy S23 Ultra, which combines 16 pixels in 1 to generate detailed photos in dark environments.
The downside is that pixel binning reduces image resolution, which is why the technique is only viable in cameras with many megapixels.
How can cell phones focus in the dark?
Low light levels make focusing difficult, so optical image stabilization (OIS) and sensor-based image stabilization (IBIS) are allied with night mode photos. Cameras with this technology are able to move lens elements to compensate for involuntary user movements that leave the image blurry or out of focus.
The ToF sensor, found in phones like the iPhone 14 Pro, uses infrared light to calculate the camera’s distance from an object. With the technology, focusing is done faster and more accurately, even in dark environments, which also makes it useful for night mode.
How does night mode image processing work?
Night mode also involves image processing, that is, processing the information that makes up the photo. This step is important not only for generating sharp images, but also for removing noise and adjusting colors.
In smartphones with large processing capabilities, this work is done with computational photography techniques. Among these is the recording of several photos in sequence and with different exposures. Then they are combined to reduce noise.
Another technique is to increase the shutter opening time to capture more light. Next, the ISP (Image Signal Processor) adjusts parameters such as brightness, white balance and color depth to remove or smooth out imperfections.
The result obtained is not always satisfactory. Some night shots may lose definition or turn whitish in post-processing. This is often caused by ISP throttling or lack of stabilization.
The biggest challenge faced by manufacturers is the fact that the compact size of mobile phones requires them to be equipped with small image sensors, which capture less light.
However, brands like Apple and Samsung manage to generate more and more convincing photos on their mobile phones. To do this, they combine ISP, image sensors and lenses with artificial intelligence and other advanced features.
Does my phone’s night mode work on videos?
Yes, but few smartphones offer a native night mode for video recording, like the Xiaomi 13 Pro and Vivo X90 Pro.
Some mobile phones offer the function linked to another function. This is the case of the iPhone 12, which makes time-lapse recordings with night mode. Just secure your device to a tripod or solid surface and open the “Time-lapse” option in the camera app. Night shots will be optimized automatically.
For other situations, the advice is to use specific applications for night mode videos, such as NeuralCam Night Video (for iOS).
How to use the manual mode of the mobile phone for night photos?
Night mode does not always provide satisfactory results or is available on mobile phones. In these circumstances, the solution is to make manual adjustments in the camera app.
In general terms, setting your mobile phone camera to manual mode for night scenes requires increasing the exposure time to 30 seconds, as well as smoothing the ISO value to avoid image blur and excessive noise.
Using manual focus is also important, preferably with a tripod or other way to stabilize the cellphone.
How night mode works on your phone’s camera
Source: Terra
Rose James is a Gossipify movie and series reviewer known for her in-depth analysis and unique perspective on the latest releases. With a background in film studies, she provides engaging and informative reviews, and keeps readers up to date with industry trends and emerging talents.
