索尼 a7R II 评测

这款全画幅无反紧凑相机拥有 42.4 百万像素背照式 CMOS 传感器和最高 102400 的 ISO 感光度等极其强大的规格，作为即拍即得的设备，它的实力不容小觑。阅读我们对 Sony a7R II 的完整评测，了解更多关于其功能的信息，并查看它从相机直接拍摄出的图像效果。

Design and Construction

同样来自紧凑型相机的 alpha 7 系列，a7R II 与我们在 SEA 发布期间短暂玩弄过的 a7 Mark II 几乎外观相同。

其机身大部分采用镁合金，现已改进防潮封装，并配备加固的镜头卡口，能够容纳更大、更重的镜头。

在机身顶部右侧，我们可以看到用于拍摄模式和曝光的拨盘。此区域还配备了可编程按钮，便于轻松切换不同的拍摄设置。内部，快门采用减振设计，每次帘幕移动时产生的声音更小。

连接端口和插槽被战略性地放置在机箱周围。右下侧是 miniSD 卡槽，发射器底部是电池组。打开左侧的盖子即可看到用于与其他电子设备连接的端口。

控制与人体工学

凭借按钮和拨盘的布局，操作 a7R II 非常轻松舒适。握持时，即使机身紧凑，也能感受到它的分量。这并非全是缺点，适当的重量有助于拍摄时保持稳定。

正如我们在 a7 Mark II 中提到的，机身现在感觉更深，比之前的型号更舒适，手握时更贴合。前端，我们看到旋钮被重新定位，距离快门释放按钮约一英寸，位置合理且符合人体工学。

下一页：取景器和实时取景、自动对焦性能以及噪点和 ISO 性能

取景器和实时取景

a7R II 配备了 0.5 英寸 236 万点 XGA OLED 电子取景器（EVF），能够忠实呈现相机将要捕捉的画面。通过取景器还能看到内置的 3 轴水平仪，帮助保持地平线平直。最后，它拥有公司称之为 ZEISS T 涂层的技术，可降低表面反射，提升观感。

在实时取景或查看拍摄画面时，配备了 2.95 英寸、120 万像素的 TFT LCD，能够上下倾斜，提供更灵活的拍摄姿势。色彩还原和曝光均十分准确，使用实时取景时完全可以依赖屏幕。

我们注意到，轻微的移动会使电子取景器的传感器关闭显示。这导致我们必须多次确保没有任何物体进入传感器范围，否则即使在拍摄前调节设置时，显示器也会关闭。

自动对焦性能

a7R II 采用快速混合自动对焦系统，拥有 399 个相位检测点和 25 个对比度检测点，公司声称覆盖了 45% 的整体画面面积。其对焦速度也比前代提升了 40%。的确，我们在设备上体验到了快速的对焦时间，但在高速拍摄时仍不够可靠。例如，我们无法在一辆快速驶过的炫目跑车面前立即掏出相机并开始拍摄。

为了保持主题聚焦，a7R II 采用了 5 轴 SteadyShot 技术，可补偿垂直、水平、俯仰、偏航和滚转运动。这项技术已经存在一段时间，并被证明对手抖自然的用户非常有用。

噪声与 ISO 性能

这款紧凑型相机的感光度范围可从 ISO-50 直达惊人的 ISO-102400。无需多言，我们可以假设感光度是这款无反相机的强项之一。

这项备受赞赏的功能效果显著，让我们想在夜间拍摄更多。但别再用文字说服你了，直接看看我们在 ISO-6400 下拍摄的样片：

Here's a closer look at the image:

如您所见，放大后可以看到数字噪点，虽然与其他相机在此 ISO 值下相比并不十分明显。这使得相机对爱好者非常有吸引力，因为他们可以通过提高 ISO 在低光环境下轻松拍摄，而无需担心噪点干扰。

Next page: Image and Video Quality, Battery Life, and Conclusion

Image and Video Quality

Having the world's first backside-illuminated full-frame sensor on 35mm format and a BIONZ X image processing engine for more natural images with minimal noise, the a7R II produced exceptional images for a compact shooter. Colors are naturally vibrant, details are very much intact, and its low-light clarity is just satisfying.

Below are some sample photos using the 35mm lens that Sony lent us. Keep in mind that these are raw images and haven't been altered in any way. Some of the effects seen here are all made in-camera by tweaking the settings.

We have uploaded more sample photos straight out of the a7R II in this post -- Gallery: Walking Around New York City With a Php155K Camera.

As for video capabilities, this able shooter could record up to 4K resolution (QFHD at  3840 x 2160) at either 30 or 24fps. We were able to capture footage with lively hues and smooth edges, while jaggies are kept to a minimum. Apart from that, it also records Full HD video at 60, 30, and 24fps.

We went around Times Square in New York City and took some sample videos at its highest resolution possible. Here are the results:

Battery Life

While going around in a foreign city as a tourist, you could safely say that we were using the camera every once in a while for any interesting/new things we see. And with that frequency of shooting, the a7R II was able to last a day and a half of usage before its battery got juiced out. That's not so bad considering all the things happening inside to produce those shots.

Charging time is normal and similar to the previous cameras we've tried before -- taking a couple of hours to recharge from 0-100%.

Conclusion

The Sony a7R II undoubtedly has what it takes to be one of the best full-frame mirrorless cameras out in the market. It’s a fitting example of what a camera should be with all the useful features squeezed inside a compact body.

With it, you have a capable photo device that isn't restricted by low light scenes, while also being able to shoot videos  at an impressive 4K resolution. Of course, with those chunky specs also come a steep pricing. The a7R II has a price tag of Php154,999 and that's only for the body (lens excluded).

Sony a7R II specs and key features:
42.4MP Backside-Illuminated CMOS sensor
Sensor Type: Full-frame (36 x 24mm)
Bionz X Image Processor
14-bit uncompressed RAW format
Contrast detect + on-sensor Phase detect AF w/ 399 AF points
ISO 50 – 102400
30 sec. – 1/8000 sec. shutter speed
5fps continuous drive
Optional External Flash via Hot-shoe
2.4M-dot Electronic Viewfinder
0.78x Magnification, 100% coverage
2.95-inch articulating 1.2M-dot TFT LCD
4K video recording at 30/25/24fps
1080p video recording at 24/60fps
MPEG-4, AVCHD, XAVC-S video formats
Wi-Fi 802.11 b/g/n
NFC
SD / SDHC / SDXC
RAW + JPEG file format
Micro-HDMI
NP-FW50 Lithium-Ion battery, rated for 290 shots
Dimension: 127 x 96 x 60 mm
Weight: 625g

What we liked about it:

• Compact, robust body
• Produces vibrant and detailed images
• Astounding ISO sensitivity
• Easy to navigate dials and instrumentations
• Snaps silently
• Satisfactory AF

What we didn't like:

• EVF sensor is sensitive
• Record button is oddly-placed
• Takes a while to pair with other devices using Wi-Fi