Pentax K-3: And now for something completely different (hands-on)
For its latest top-of-the-line dSLR, the K-3, Pentax overhauls the/IIs inside and out: it's got a new sensor, new body design, new AF system, new metering system, and improved performance. I had a chance to spend some time with an early model that displayed some not-unexpected firmware wonkiness that prevent my reporting on image quality or performance, but it looks like a promising start with some interesting twists. As for Pentaxians who don't need the latest and greatest, the K-5 II and IIs will remain in the line at lower prices, although Pentax hasn't announced what those will be yet.
Like the IIs (and the Nikon D7100), the K-3's new 24MP drops the optical low-pass filter (OLPF) entirely. But sometimes you want the slight blurring effect of the OLPF, especially if you know moire will be a problem -- and Pentax takes a novel approach to addressing that concern. The K-3 can use its sensor-shift shake reduction mechanism to slightly offset the pixels with circular, horizontal, or vertical movements. It doesn't seem to be available in movie mode, however. To compensate for the increased vulnerability of the sensor, there's now a vibrating piece of coated glass over it for dust protection and removal.
The new autofocus system unfortunately doesn't have any Live View optimizations, though Pentax says that five of the AF sensors are specifically for low light, and even the preproduction model was able to lock focus in some pretty dim conditions. Pentax also takes a leaf out of Nikon's and Canon's book, implementing a more granular, RGB metering system and using the data from the light meter to supplement the autofocus. Like the Canon EOS 70D, it now implements Zone Focus, though it doesn't display the zone -- just the selected focus point -- on prefocus. It does seem to select the center of the zone more often then not (which is good). The camera retains the expanded area AF as well.