Sony HX200V 18.2MP Technology

To the overwhelming beauty of the 18.2 million pixel effective (*) the best in the industry. Back-illuminated CMOS sensor "high sensitivity" Sony's "Exmor R (Exmore are)"

And here sony says how it works..

CMOS sensor "Exmor R" Enable newly developed 18.2 million pixel, high-dimensional cooperation in the engine "(Bionzu) BIONZ" image processing. In addition, noise-reduction technology has evolved by (Adaptive Noise Reduction), high-quality performance overwhelming. In addition, by "back-illuminated technology," Sony's proprietary, improved light sensitivity was the task of the compact camera. To achieve high sensitivity of (*), even in dark scenes, such as night or indoors, you can take a picture strikingly beautiful about two times compared to the previous model.

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