Smartphones boasting “dual cameras” are becoming more common, and news that they will feature on the just-announced iPhone 7 Plus indicates the arrival into the mainstream.
But while dual cameras may stem from efforts to improve picture quality, it has the potential to lead us down much more interesting paths: the real story may be that Apple is using dual cameras to position itself for the augmented reality world ushered in by the Pokemon Go phenomenon.
Augmented Reality, or AR, has for years been a solution in search of a problem.
In the last few months, Pokemon Go has been the app to take augmented reality into the mainstream after years in the wilderness, and with Apple’s Watch now able to run Pokemon Go directly, the company surely hopes it has found the answer. The new dual camera system in the iPhone 7 Plus may just be the platform on which to expand fully into AR.
Manufacturers present dual cameras as a means to help smartphone cameras behave more like a professional digital single lens reflex (DSLR) cameras – the digital derivatives of the camera design popular since the mid-20th century. The main reason for the rise in dual cameras is physical necessity. It’s not possible to attach a professional-grade zoom lens to a mobile phone – today’s smartphones are just too tiny.
Alternatively, creating camera zoom features in software quickly runs into limits of picture quality. But as lens hardware falls in cost, adding another physical camera is now feasible, with software switching between the two and interpolating images from both cameras.
Twin cameras at different focal lengths, for example one wide and one telephoto, offer several benefits. The telephoto lens can be used to compensate for the distortion common in wide angle lens by blending the flattening effect of a long lens.
Having two slightly different types of sensors gives better dynamic range, the range of light and dark in scenes within which a camera can capture detail. Greater dynamic range and information about the scene give sharper details and richer colour.
Relying on real optical lenses rather than software to zoom reduces the digital noise that makes images grainy. And given less noisy images with more image data, it’s possible to improve the quality of software zoom.
The twin 12 megapixel cameras on the rear of the iPhone 7 Plus are the result of a Apple’s canny purchase of camera module manufacturer Linx in 2015. Building on Linx’s technology, Apple has incorporated a wide angle 28mm lens and a telephoto 56mm lens into its phones.
The camera software uses either or both the dual cameras to provide the best quality images, while making this process transparent through the iOS touch interface that offers live movement between wide angle (1x), telephoto (2x), and software zoom now up to 10x.
Building stereoscopic scenes
As appealing as this may be, adding a second rear camera offers a much more interesting set of possibilities. Having two slightly different viewpoints means live images can be processed for depth information per pixel captured, so that images gain an extra dimension of depth data.
… read more of this article by Jeffrey Ferguson on Business Insider