With Internal 4K, the a7R II Is Sony’s New Flagship Mirrorless Camera

Sony's just-announced a7R II mirrorless camera is looking to carve out a serious niche in the market, utilizing a brand-new 42-megapixel (7952×5304) full-frame back-illuminated CMOS sensor and offering on-board 4K UHD video recording.

The a7R II's 4K implementation uses XAVC S encoding at a bit rate of up to 100 Mbps, and filmmaker-friendly features include Picture Profile, S-Log2 Gamma and S-Gamut, timecode, and clean HDMI out. Sony said it had improved the amount of light collected by the new sensor through a "gapless on-chip lens design" and an "anti-reflective coating on the surface of the sensor's glass seal," allowing it to offer an expanded ISO range that peaks at 102400. The a7s, also a lust object for filmmakers, beats that with a high ISO of 409600, owing to larger photosites on a lower-resolution sensor—but the a7s does not record UHD video internally.

The a7R will shoot in two modes: in Super 35mm crop mode, the camera oversamples its 4K image from a region of the sensor with about 15 megapixels (5168×2912), or 1.8x as many pixels as UHD (3840×2160), to reduce moiré and aliasing without pixel-binning; in full-frame mode, the full width of the 35mm sensor is used to create the 4K image. Many users are expecting that the full-frame 4K mode will seriously reduce the visibility of rolling-shutter artifacts. We'll see.

Sony released this sample of 4K video from the a7R II.

The camera body is built from magnesium alloy for sturdiness and has a new XGA OLED viewfinder with a double-sided aspherical lens for a 0.78x magnification factor. For monitoring, Sony introduced the CLM-FHD5, a five-inch LCD monitor with peaking, false-color and S-Log display assist options. The a7R II also has a five-way image-stabilization system that will help address rotational shake, or roll, in video recording.

What's missing? Well, the a7R II will never be the low-light king. That honor remains with the a7s, which trades resolution (its sensor is only 12 megapixels) for big gains in sensitivity. It'll never be your slow-motion camera, and it won't do 60p UHD, either—the UHD recording is limited, unfortunately, to 24p, 25p, and 30p. 

In related news, Sony said its expanding line of alpha-mount glass now includes 12 full-frame lenses, with the number expected to climb to 20 by early 2016. 

Sony says the a7R II will ship in August for a price of about $3,200.

Source: With Internal 4K, the a7R II Is Sony's New Flagship Mirrorless Camera