The Pentax K-3 hit all the right notes in our review, which earned it our highest recommendation as well as a 2013 Reader's Choice Award from our audience. The time has come for a successor to appear, and that camera is the K-3 II.
With the K-3 II, Ricoh has taken what made the K-3 a great DSLR - a rugged, weather-sealed body, great image quality, large viewfinder, dual memory card slots, and more - and improved many of its weaker points.
To improve image quality, Ricoh has added a feature known as Pixel Shift Resolution (more on that later). Continuous subject tracking autofocus has been tweaked (though that's hard to quantify until we've tested it), and the K-3 II's in-body image stabilizer now provides 4.5 stops of shake reduction (using the CIPA standard). A GPS has been added, but the K-3's built-in flash has been removed in the new model.
As is the case with most Pentax-branded DSLRs, you get a lot of bang for the buck. The K-3 II will be priced at $1099 body only, which is a few hundred dollars less than the likes of the Canon EOS 7D II and Nikon D7200.
Pixel Shift Resolution:
One of the key features that sets the K-3 II apart from its predecessor is its 'Pixel Shift Resolution' mode. This is a sensor-shifting multi-shot mode, not entirely unlike the one offered by the Olympus OM-D E-M5 II only, but with the key difference that the K-3 II's system does not increase linear resolution.
The K-3 II's system takes four images with a whole pixel shift between each shot. This allows the camera to overcome any color limitations of its Bayer sensor: the sensor is moved so that a red, blue and two green sensors element have captured an image at each location, meaning every output pixel is made up from full color information.
This has two direct benefits: firstly it provides images with full color resolution, meaning better definition at borders between areas of different color, and elimination of false color aliasing (like moiré) from high-frequency patterns. Secondly, as a result of sampling the same point four times, the images will have greatly improved noise characteristics. The other benefits over the Olympus system is that it could be faster, as it only requires four exposures, rather than eight, so there's a lower likelihood of subject movement while the shots are being taken, and that there's no ambiguity about the optimal size to render the end result.
http://www.us.ricoh-imaging.com/dslr/K-3_II#!product-specs
http://www.dpreview.com/articles/7238180077/hands-on-with-the-pentax-k-3-ii?slide=10
