Video: Samsung shows off the tech behind its 108MP ISOCELL HM3 image sensor

One of the main features of Samsung's latest flagship smartphone, the Galaxy S21 Ultra, is naturally its 108MP primary image sensor. Besides the display and form factor differences, the 108MP image sensor is a key differentiator between the S21 Ultra and the standard Galaxy S21.

The image sensor used for the S21 Ultra's 108MP main camera is a

Samsung ISOCELL HM3 sensor

. Samsung released a video this week describing the image sensor and what makes it unique. While the video is, at least in part, marketing material, it nonetheless sparks some interesting conversations about Samsung's impressive smartphone camera technology.

As stated in Samsung's video, 'every pixel is isolated with ISOCELL 2.0 technology to improve light sensitivity and color fidelity.' The image sensor includes "Nonapixel" technology, which Samsung says "improves performance in low light conditions." When shooting in dark surroundings, the image sensor automatically combines nine pixels into one large pixel to produce low-noise images in low-light situations.

Samsung's "Nonapixel" technology allows the image sensor to combine pixels in addition to single-color pixel arrays to improve low-light performance. Image credit: Samsung

A remosaicing algorithm rearranges all 108M pixels under bright conditions to use high resolution. The sensor's Smart-ISO technology allows it to switch seamlessly between Low ISO and High ISO shooting modes, which Samsung says maximizes detail in bright, low-noise conditions when shooting in low light situations. Smart-ISO Pro combines sensor readings from low and high ISO shooting modes to produce a single image with 12-bit color depth and wide dynamic range when shooting in mixed lighting. A shifted HDR mode uses a rolling shutter to combine images taken with different shutter speeds.

Samsung's ISOCELL HM3 image sensor has many fascinating photographic features. You can see the main features in this graph, courtesy of Samsung. Click to enlarge.

These advanced technologies don't mean much if the camera can't focus accurately, which is why Samsung has added its new Super PD Plus AF technology. Samsung says newly designed microlenses on the phase-detection focusing pixels improve autofocus speed and accuracy, even in low-light conditions. The Korean company released a few tech videos earlier this year, including one that discusses ISOCELL 2.0 technology and another that describes Smart-ISO Pro. Both videos can be seen below.

A smartphone's photographic capabilities and performance go beyond megapixel count and high-tech image sensors. Real-world usage matters too. In February we have

discovered

a photographer video comparing the S21 Ultra to a Canon 1DX II DSLR camera.

For more on the Samsung Galaxy S21 Ultra, refer to

our launch cover

.