Samsung's Dual Pixel auto focus explained and why it's the best out there right now
Yesterday Samsung announced all the juicy
details about its upcoming Galaxy S7 and Galaxy S7 Edge smartphone and for us
geeks, the camera was one of the most interesting bits of the announcement.
Samsung is using the 1/2.5" Sony IMX260
sensor. Compared to the Galaxy S6, the new sensor has bigger individual pixels
(1.44 microns) and the optics have a wider aperture (f/1.7). Samsung has also
shaved off some of the height of the camera hump on the back, and it's now down
to just 0.46mm. The Galaxy S7 duo camera also comes with something they call
Dual Pixel autofocus.
Among these tidbits the Dual Pixel autofocus
technology took a back seat but we think it's the most advanced aspect of the
module. In its essence, Dual Pixel is the same Phase Detect technology that
top-tier smartphones, DSLRs and mirrorless cameras have been using for quite
some time in one form or the other.
However, Samsung chose to name it differently
from regular Phase Detection autofocus because their latest implementation is
unlike anything we've seen before on a smartphone. It's Phase Detection 2.0 for
the smartphone world.
We've seen our share of smartphones touting
Phase Detect autofocus last year. They all use a hybrid autofocus solution,
which combines the benefits of contrast detect and phase detect autofocus
systems. Where Phase detection really shines is in good lighting where it
allows hybrid autofocus systems to acquire accurate focus faster than
conventional contrast detection systems.
In its smartphone implementation phase
detection usually relies on special photodiodes embedded into the pixels on the
sensor. Apple even went as far as branding them as 'Focus pixels' when they
announced the iPhone 6 - a proprietary term they came up with to describe
conventional technology.
These photodiodes, however, are scattered few
and far between across the sensor surface and only as few as 5-10% of the total
number of sensor pixels are phase detection enabled.
Now, with Dual Pixel technology, Samsung has
embbeded a phase detection photodiode in each and every pixel on the camera
sensor.
The
camera can quickly obtain accurate focus on any objects in the frame regardless
of its position. The system works impressively well - even by dedicated camera
standards.
And
it's lightning fast too - take a look:
Dual Pixel technology isn't new - it has
already been featured in leading DSLR and mirrorless camera sensors, but it's
superior to anything we've seen on a cameraphone. One thing's for sure - mobile
photography is about to ascend to a whole new level this year.