Adding fiveaxis image stabilization to a full-frame ILC
When Sony launched its interchangeablelens compacts in 2010, the company changed its approach to image stabilization. Instead of the sensorbased system used in its Alpha-series DSLRs, it built optical stabilization into its ILC lenses. But Sony hardly abandoned sensor-based IS—in fact, it kept innovating, creating the first stabilization system for full-frame image sensors, which it debuted in the a99. Now, with the a7 II, Sony introduces a new full-frame sensorbased five-axis stabilization system that can operate on its own or work in conjunction with the optical stabilization in some lenses.
We were quite impressed with the results, as well as the other changes Sony made to this popular camera. Though it still bears a striking resemblance to the other Alpha-series ILCs, the a7 II ($1,698, street, body only) required an extensive redesign to add the floating sensor capabilities. Along with this came a more prominent grip with better ergonomics for the shutter release and front command wheel. Likewise, Sony beefed up the lens mount, replacing some of the plastic in the original a7's mount with metal. Plus, it enhanced the autofocus with better tracking capabilities and new algorithms for speedier focusing. Video capture also steps up to the XAVC S codec, allowing 1920xl080p60 capture at up to 50 Mbps. We were eager to run the new camera through the Popular Photography Test Lab and our usual rigorous field testing.
In the Test Lab
Sony’s a7 II achieved an Excellent rating in overall image quality from ISO 50 through ISO 1600. To arrive at that result, however, we did veer slightly off of our normal testing procedure. We normally test TIFFs converted from RAW files using the conversion software that ships with the camera, but we couldn’t do that here because of a software bug (we encountered the problem while testing the A77 II last fall and it has not yet been resolved). Since Adobe Photoshop Lightroom 5.7.1 and Camera Raw 8.7.1 offer official support for this new camera, we used ACR for file conversion and proceeded as we normally do for cameras that ship with Adobe’s software. This means we applied 25, 50, and 75 percent of Adobe’s luminance noise reduction and weighed the results against resolution to determine how much reduction to apply at each ISO.
We ended up with 25 percent noise reduction from ISO 50 through 800 and 50 percent from ISO 1600 through 25,600. This leaves plenty of room for additional noise reduction should you feel the need, and it tracks closely to the noise results we saw when using Sony’s software for our test of the original a7.
Compared with Samsung’s NX1, which does ship with Lightroom 5, the a7 II showed cleaner results at ISO 800 and lower, and very slightly higher numbers at ISO 1600 and above. However, the NX1 ended up with 75 percent noise reduction at those higher ISOs, which, along with the noise still present after reduction, caused the NX1 to score lower resolution numbers than the a7 II at both ISO 12,800 and ISO 25,600.
Speaking of resolving power, the a7 II easily earned an Excellent rating in our resolution test at its lowest sensitivity of ISO 50, where it delivered 2720 lines per picture height. The score slid to a still-healthy 2680 at ISO 400. At ISO 1600, where noise reduction stepped up to 50 percent, the a7 II captured 2575 lines, and only at ISO 6400 did resolution drop to the lowest limit of our Excellent rating at 2500 lines. The camera’s top two sensitivities of ISO 12,800 and ISO 25,600 saw 2460 and 2320 lines, respectively, rating Extremely High.
In our color accuracy test, the a7 II earned an Excellent rating with an average Delta E of 5.6. This improves upon the 7.9 that Sony’s software delivered with the a7 and beats the NX1’s result of 7.5. However, all three of these results are enough for an Excellent rating and should be considered to deliver a wonderful re-creation of color. (We expect that given the persistent popularity of highly saturated color rendition, most photographers will wind up making the color less accurate in their final images than what they see coming straight from the camera.)
In our image stabilization test, which we conducted using Sony’s stabilized FE 70–200mm f/4 G OSS lens zoomed to 200mm, the a7 II averaged 3.5 stops of shutter speed leeway. (We used this lens because it was the only native FE-mountlens available to us during our testing period that had such a system used the moving lens elements in the 70–200mm to compensate for motion in pitch and yaw, while the sensor shifted to compensate for lateral and vertical motion as well as for roll. The result was quite impressive, especially considering that this was the debut of a newly designed stabilization system.
In the Field
The a7 II’s redesigned grip is a big improvement over its predecessor’s. It not only offers a much more comfortable way to hold the camera, but also positions the shutter release in a significantly better ergonomic position. As on most DSLRs, the new ILC’s shutter button is angled slightly downward at the front and is located on top of the grip instead of the main camera body. As such, you don’t have to reach awkwardly backward to operate the shutter; instead your index finger lands in a more natural-feeling spot, which should put less strain on your hand. These design improvements make the a7 II more comfortable to use for longer periods.
The control interface remains very similar to that of the a7, but moving the shutter button let Sony add an extra customizable button on top. With two command wheels and ample opportunity to customize the controls to our liking, we had no trouble switching settings on the a7 II while out shooting.
Likewise, the video recording remains basically the same as with the a7, topping out at 1080p at 60fps, though it uses the newer XAVC S codec instead of AVCHD. You can also still use the HDMI jack to send a clean, uncompressed signal to an external recorder.
In our test of the a7 in 2013, we noted its burst rate, a meager 2.5 frames per second, as one area that could be improved. The a7 II boosts that to 5 fps and lets you shoot up to 77 large fine JPEGs, 25 RAW files, or 23 RAW + JPEG frames before the buffer fills. That’s fewer than the 31 RAW shots the older model could get per burst, but the a7 II’s faster frame rate also means that fewer shots can be cleared from the buffer to the memory card while shooting. Especially for a camera of this size, we’ll take 25 frames at 5 fps any day.
Autofocus feels faster than in the a7, and the AF tracked moving subjects well. (The 70–200mm f/4 zoom focused especially fast for a lens spanning this range of focal lengths.) The tracking AF now shows an array of small green squares indicating where in the scene the camera is looking as it adjusts focus. Basically the same method Sony uses in its a6000, it provides a somewhat similar experience to shooting with Nikon’s 3D tracking AF. It’s reassuring as you shoot to see that the camera is indeed holding its focus on the person or object that you want to track.
Sony’s wireless capabilities haven’t changed much since the a7. We easily paired the a7 II with a Samsung Galaxy S3 to share photos and let the smartphone control the camera.
The Bottom Line
If you’ve been eyeing the original a7 but holding off buying, the a7 II should definitely be your new object of desire. But we’re not sure that current a7 owners should run to replace their cameras. If you use tracking AF a lot and really need sensor-based IS, then you might consider it. Otherwise, you may be better off waiting another year or two for the next update.
However, if you would like to enter the ILC world for the first time, the Sony a7 II certainly belongs on your short list. This new full-framer represents one of the best combinations of small size and high-level performance you can find in a camera today. —Philip Ryan
Specifications
IMAGING: 24.3MP effective, full-frame Exmor CMOS sensor captures images at 6000x4000 pixels with 14 bits/color in RAW mode
STORAGE: SD, SDHC, SDXC, Memory Stick PRO Duo, PRO-HG Duo, XC-HG Duo. Stores JPEG, ARW RAW, RAW + JPEG
VIDEO: Up to 1920x1080p60 XAVC S/AVCHD v2/MP4; built-in stereo mic, stereo minijack mic input; continuous AF; maximum clip length approximately 29 min 59 sec
BURST RATE: Full-sized JPEGs (Fine mode): 5 fps up to 77 shots; RAW (14-bit): 5 fps up to 25 shots when using a UHS-I memory card
AF SYSTEM: TTL hybrid phase/contrast detection with 25 selectable contrast focus points, 117 phase detection points. Singleshot and continuous with predictive focus tracking, face detection
SHUTTER SPEEDS: 1/8000 to 30 sec (1/3-EV increments); shutter life not rated
METERING: TTL metering using 1,200-zone sensor with Multi-segment (evaluative), centerweighted, and spot (size of spot not specificied) metering; –1–20 EV (at ISO 100)
ISO RANGE: ISO 50–25,600 (in 1/3- or 1-EV increments).
FLASH: No built-in flash; Multi Interface shoe accepts accessory flashes
EVF: Fixed 0.5-inch eye-level 2,359,296-dot OLED with 3-step brightness adjustment; 100% accurate; 0.71X magnification
LCD: Tilting 3-in. LCD screen with 1,228,800-dot resolution; 5-step brightness adjustment
OUTPUT: Hi-Speed USB 2.0, micro-HDMI video, stereo headphone minijack
BATTERY: Rechargeable NP-FW50 Li-ion, CIPA rating 340 shots
SIZE/WEIGHT: 5.0x3.9x2.4 in., 1.3 lb with card and battery
STREET PRICE: $1,698, body only; $1,998, with FE 28–70mm f/3.5–5.6 OSS lens
FOR INFO: store.sony.com