In September, Apple unveiled its new iPhone as usual.  Once again this year it was hard for Apple to keep most of the changes under wraps.  As expected, the key upgrades included removal of the headphone jack, expanded internal memory options, adding water resistance, and 2 new colors including glossy Jet Black.  What caught my eye was the rear dual cameras of the iPhone 7 Plus.

It’s not an eye opening surprise, since it had been rumored for a long time.  In addition, it was foreshadowed in early 2015 when Apple acquired a small Israeli camera-technology company called LinX.  The company was developing cameras which create 3-dimensional image mapping and technologies claiming that its array camera lineup can improve low light performance as well as general image quality.

It is meaningful to the industry when the very latest Apple iPhone, the trendsetter of the market, incorporates this adaptation. It is a signal that the technology will proliferate and dual (or multi) camera modules are here to stay. In this article, we will review how various companies have been trying to add new value to the smartphone by implementing dual-camera technologies.

Dual Camera before 2016

In 2011, LG and HTC launched a new smartphone named the Optimus 3D and HTC Evo 3D, respectively. They utilized dual cameras capable of filming 3D video. In fact, it was strongly inspired by the booming trend of 3D of the times, led by the hit movie ‘Avatar’.  The Optimus 3D’s major selling point was its ability to enjoy 3D movies without wearing any additional glasses.

Unfortunately, most of the 3D content quality did not meet users’ expectations.  Due to its limited number of target consumers, the Optimus 3D’s sales performance was disappointing—similar to the future of 3D TV.

In 2014, HTC adopted dual cameras for its HTC M8 flagship.  The device provided various editing features including UFocus (an option to pinpoint target what is in focus and ability to blur surroundings), Dimension Plus (ability to view images in 3D), and Sketch (which transformed surroundings in sketch-like effect while the focus remained same).  All this post-shot editing was enabled by the secondary camera which recorded depth information upon shooting.

  

HTC has also implemented dual cameras on its M8 Eye and Butterfly 3.  Huawei also adopted a dual camera experience in the Honor 6 Plus, which had similar functionality to the HTC M8.    

Dual Camera in 2016

This year, dual cameras are being implemented with various use cases & marketing:

In collaboration with the world famous camera brand Leica, the dual camera of Huawei P9 (See here), capture two images, one in color and the other in monochrome. Then, the 2 images are combined to create one final image utilizing more luminance data provided by the monochrome sensor, which is known to capture 2.5~3 times more light than a color sensor. Huawei is driving this dual camera configuration into its mid-tier products, the Honor 8 & Honor V8 (though the Leica logo no longer appears on the body).

The combination of the color and monochrome sensor for dual camera is recently spreading to other vendors. Xiaomi, so-called Apple of China, implemented the dual camera setup with its “Plus” model of the flagship Mi 5S just like Apple did with iPhone 7 plus although the configuration is different. Mi5S Plus is the first smartphone using Qualcomm’s Clear Sight technology which merge and process image data from both cameras, one for color and the other for monochrome, taking advantage of the Spectra ISP(image signal processor) in Snapdragon 821. Also, LeEco’s Cool1, launched in August, features the similar dual camera functionalty as Huawei P9 at the price of about $170 for basic model.

LG is taking a different approach than that of Huawei. The two camera lenses of the LG G5 have different view angles from each other. One is 78 degrees and the other is 135 degrees, enabling super-wide-angle shooting. Also, using 2 lenses together, it offers ‘Pop Out Picture’, an intriguing feature that can apply various editing effects such as blur and distortion. LG’s latest model, the V20, and entry level model, the X Cam, both have adopted dual cameras similar to G5 as consumers are showing positive feedback on super-angle cameras, especially good for ‘groufies’ (aka panoramic selfies).

  

Lastly, the dual camera on the iPhone 7 Plus (See here) consists of a 12MP wide angle lens & a telephoto lens. It’s the telephoto lens, which supports two times the optical zoom effect, that makes it unique. Optical zoom enables screen enlargement without any image quality loss, but usually results in a thicker form factor to secure enough room for the telephoto lens glass surface to move.

iPhone 7 Plus managed to provide the optical zoom effect without adding much thickness to the body by analyzing two images and merging them using sophisticated algorithms with the help of ISP(image signal processor). Consequently, the camera feature of iPhone 7 plus heavily relies on the image processing hardware, and this seems to be one of the reasons that iPhone 7 plus has 3GB of RAM whereas iPhone 7 has just 2GB.

Apple named its out-of-focus background (or Bokeh) feature as Portrait Mode.  The feature was not included in the launch OS software of the iPhone 7 Plus, but will come through an OS upgrade (You can experience it in iOS 10.1 Beta if you want). Bokeh effect already existed in the HTC One M8, but with the combination of the telephoto lens suitable for a portrait picture and the human recognition feature, Apple is expected to greatly improve portrait photos with much more enhanced quality.

Table: Summary of dual camera smartphone usage scenarios

		HTC One M8	Huawei P9	LG G5	Apple iPhone 7 Plus
Image
Date of launch		March 2014	April 2016	April 2016	September 2016
Camera1	Resolution	4MP	12MP	16MP	12MP
	Aperture	F2.0	F2.2	F1.8	F1.8
	OIS	No	No	Yes	Yes
Camera2	Resolution	4MP	12MP	8MP	12MP
	Aperture	F2.0	F2.2	F2.4	F2.8
	OIS	No	No	No	No
Dual Camera Feature		Bokeh (Common in dual camera smartphones)	RGB+Monochrome	Ultra-wide angle (135 degree)	2x Optical Zoom (56mm) for enhanced Portrait mode

Dual cameras are not yet mainstream and remain a rather new feature.  The secondary camera added for special features still needs technical improvements such as low aperture value and OIS feature, in our view. The share of smartphones with dual cameras are only 2.5% of the overall smartphone market as of July 2016 according to our Monthly Premium Market Pulse.

With the iPhone 7 Plus finally in the market, however, it will certainly help to promote dual camera penetration. Commoditization is happening on all fronts and differentiation is hard to achieve in today’s market. The camera feature is one of the most valued features and dual cameras are now a more recognizable feature that can easily help a device stand out from the crowd. Xiaomi’s Redmi Pro and TECNO’s Phantom 6 are such examples under $300 price segments as they employ the basic dual camera setup.

Perhaps the real potential of dual or multiple camera sensors is the depth information which is expected to play important roles in AR technology being developed for future use cases. For example, Lenovo’s PHAB 2 Pro, the first Google’s Tango-enable smartphone, will utilize the RGB camera, depth sensing infrared camera, and motion tracking camera making it have the total of four cameras including the front camera.

Dual cameras are penetrating into wearable, too. Spectacles, a stylish sunglass from Snapchat, has two cameras positioned at the hinges on either side of the lenses (See here). In spite of some skeptical perspectives on the dual camera of today, I believe that it is only a matter of time that smartphones with 2 or more cameras become mainstream.The detailed analysis and further insights regarding Dual Camera in Smartphones is available on our research repository site.