Introduced in June, the Alpha a7R II is the flagship in Sony’s line of full-frame mirrorless cameras. It combines still and 4K video shooting in a compact package that easily distinguishes it from competitors. The heart of this camera is a 35mm full-frame (35.9mm x 24.0mm) back-illuminated Exmor R CMOS sensor that resolves at a whopping 42.4 megapixels. With an ISO range of 100 to 25600, it very nearly sees in the dark. The interchangeable lens camera (E mount) includes internal five-axis image stabilization, upgraded auto-focus features, and the ability to record 4K video in multiple formats including Super 35mm (without pixel binning) and full-frame format.
I was present at the camera’s rollout, where Sony representatives touted the video features but placed greater emphasis on the a7R II’s still photography capabilities. Since the a7R II comes from Sony’s still imaging division, that focus is not surprising. It wasn’t until I got the camera in hand that I discovered the true power of the a7R II for professional video production.
Photo by Mark Forman
Ever since we began to use full-frame DSLRs for video, we’ve had to contend with issues stemming from the fact that camera processors are not powerful enough to read all the data from a high-megapixel sensor during video shooting. Various adaptations needed to be made, including pixel binning and line skipping. Combining these compromises with the nature of the CMOS rolling shutter, we have been plagued by artifacts including skew, flash banding and aliasing.
The a7R II has a full-frame 35mm CMOS sensor that records 4K video (QFHD 3840 x 2160) in either Super 35mm crop mode or full-frame mode to internal SD cards. Sony engineers have updated the hardware to increase the rate of data output from the sensor approximately 3.5x compared to the original a7R.
In full-frame mode, the new sensor combined with Sony’s internal image processing is able to capture the image without any line skipping. In my testing, I was able to verify that shooting moving cars and pedestrians with a full-frame lens resulted in no visible skew, aliasing or flash banding. I think it is safe to declare that with the a7R II, Sony has solved that constellation of problems we refer to collectively as “rolling shutter.”
In the cropped Super 35mm mode, the camera collects data from approximately 1.8x as many pixels as 4K by using full pixel readout without pixel binning and oversamples the information to produce 4K video with minimal moiré and jaggies. I could detect ever so slightly a skew in a moving vehicle in Super 35 mode, but by no means was it comparable to what one might see with some conventional rolling shutter cameras.
Note that all of my tests were carried out with Sony’s 90mm macro f/2.8 E mount lens. It is among the sharpest still camera lenses I’ve used, with excellent contrast and close focusing. Using the lens in manual focus, though, I note what is becoming Sony’s typical fly-by-wire focusing. There is less of a manual feel to it than I (coming from using manual cinema lenses) would like, but keep in mind that the Sony FE 90mm F2.8 Macro G OSS is not a multi-thousand-dollar PL mount cinema lens.
Auto-focus is sometimes necessary when shooting in a run-and-gun situation, a typical scenario in which one might typically use a mirrorless camera. I was impressed with the camera’s ability to follow faces, but in the case of multiple faces in the frame, it does not have the ability to specify which subject to follow. I was able to track a subject well, but when that subject went out of frame and I was attempting to shoot background, there was a small amount of auto-focus hunting. Sony product managers tell me that it is possible to adjust the AF drive for AF responsiveness and tracking sensitivity. These are menu-selected options. With some experimentation, you should be able to achieve the AF performance you’re looking for.
The still image folks tout the five-axis stabilization integrated into the sensor—this onboard stabilization works in video mode, too, and it works cooperatively with Sony Alpha lenses with optical Steady Shot (OSS). When shooting with a Sony FE lens (Sony’s line of E mount full-frame-format Alpha lenses), the internal lens stabilization corrects pitch and yaw. The remainder of the stabilization takes place in the camera sensor. The camera’s stabilization also works with Sony Alpha A mount lenses without onboard stabilization via a compatible mount adapter.
When using a third-party lens through a smart adapter (I personally have E mount to Canon EF adapters from Metabones and Kipon), Sony advises to turn off stabilization on lenses that have switch-toggled IS. The IS circuitry in the sensor will detect there is no lens-based IS and will stabilize along all axes.
I was unable to test with any of my adapters but I pass along the results of Sony internal testing and study. I recommend that users perform an in-depth evaluation of auto-focus with third-party lenses and adapters before using the feature on a paying job. On other E mount cameras, auto-focus has been highly variable, ranging from close-but-no-cigar (Canon EF 24-105mm f/4L on my Sony PXW-FS7 with Metabones or Kipon) to a complete inability to auto-focus (Tokina 11-16mm f/2.8 with the same adapters).
Sony a7R II Video Specs
The a7R II shoots resolutions up to UHD 30p, which definitely places some limitations on the user. The a7R II would not be suitable for someone who needed to shoot 60p or full DCI 4K. It records UHD 30p or 24p at bit rates of either 60 Mb/s or 100 Mb/s to internal SDXC cards in Sony’s XAVC S codec. XAVC S is a consumer version of Sony’s Long GOP XAVC-L. It is the identical codec utilized in Sony’s popular a7S camera, which the a7R II leapfrogs in features. It records 1920 x 1080 HD video in XAVC S at 50 Mb/s, as well as in AVCHD at lower bit rates.
XAVC S is readable by Sony Creative Software’s Catalyst family of media prep and editing tools, as well as by Apple Final Cut Pro X, Grass Valley EDIUS and Adobe Premiere Pro. Note that Avid does not currently support XAVC S either natively or via AMA. Avid users will need to transcode. I have successfully transcoded XAVC S to ProRes using Divergent Media’s EditReady.
Also note that the XAVC S footage is 8-bit 4:2:0. That limits how far one can push these images in post before they begin to fall apart. I was able to bring S-Log2 XAVC S footage from the camera into Blackmagic DaVinci Resolve 12 beta, where I applied a LUT, did some primary and secondary correction and pulled a key, all with minimal loss of quality. I suspect that significant visual effects work or chromakeying might not produce such great results. That’s understandable. Use the camera for what it is and don’t expect it to do something it isn’t designed to do.
The a7R II has a clean HDMI output that passes an 8-bit 4:2:2 signal. If you need higher chroma subsampling, you could record this signal to any of the third-party HDMI recorders on the market.
That brings me to shooting modes and gamma. With Rec. 709 recording, the camera is able shoot an ISO range of 100 to 25600. That doesn’t mean you want to shoot ISO 25600, however; I was able to shoot up to ISO 6400 before noise rendered the image of dubious use.
The a7R II can store up to seven picture profiles for either still or video use. In a video setting, the Rec. 709 picture profile can be modified with matrix, color correction, knee, etc., just as with any other Sony camera.
I prefer the looks that can be achieved when shooting S-Log2 and then grading the footage. In S-Log2 mode, the camera cannot shoot below ISO 800 but can go all the way to 25600. It is with S-Log2 that the full dynamic range of the camera can be accessed. When shooting S-Log2, Sony has always recommended that one exposes middle gray for a target of 32 percent and white around 59 percent. Since the a7R II has only a histogram and no waveform, it might be a good idea to use an external scope or monitor/recorder with scope when learning the camera to get a feel for what “looks right.” Alternatively, some have advised using the histogram to “expose to the right” (ETTR)—that is, overexpose the image without clipping highlights. In any event, the key is always protecting the highlights.
A colorist friend observed that often “you have to cajole Sony cameras into great color.” I found that bringing the XAVC S S-Log2 footage into Resolve, applying the S-Log2 to LC709A LUT and then adjusting exposure and tweaking white balance produced very acceptable images without significant effort.
The a7R II would be useful in the exact same scenarios in which many use DSLRs: interviews, run and gun, documentary, low-budget narrative, and second unit shooting.
Note that there is no audio input. The camera has an MI shoe that is compatible with Sony’s optional XLR adapter microphone kits (XLR-K1M, XLR-K2M), which allow you to mount pro XLR microphone systems for balanced audio. Power and audio transfer through the shoe.
Product:Sony a7R II
Pros: For video, resolutions up to UHD. Ability to scan entire sensor without line skipping for absence of aliasing and rolling shutter. Five-axis stabilization even with third-party glass. Flexible auto-focus settings. Clean HDMI output of 8-bit 4:2:2 video. Compact size. OLED viewfinder.
Cons: Limited to XAVC S UHD at 30p. Internal 8-bit 4:2:0 video. More costly than other still cameras. No external audio other than through Sony MI shoe with appropriate Sony device. Limited to 29 minutes of recording per take. Battery use in video is high.
Bottom Line: As good as it gets in the mirrorless or DSLR camera world. Highly useful in many production situations. Expandable and adaptable.
MSRP: $3,200 (body only)