Sony A5100 Technical Info

By Mike Tomkins | Posted: 08/18/2014

Design

A replacement for the NEX-5T, the Sony A5100 sits between the A5000 and A6000 in Sony's lineup. In terms of design, though, it's A5000 all the way. All controls and features are located just as they were in that camera, and although the body itself has a new finish -- including a change to a leather-like texture on the hand grip -- the Sony A5100 looks very, very much like the A5000.

In fact, the only notable change we spotted is that there's now a cutout in the flash card / connectivity compartment door which provides access to the USB multi terminal without opening the whole door, to accommodate a new wired remote. Dimensions are identical, although weight has increased by a scant half-ounce (14g). And of course, the A5100 is available only in black or white, with no silver option like the A5000.

Sensor

At the heart of the Sony A5100 is the same 24.3-megapixel, APS-C sized CMOS image sensor as in the extremely popular A6000. This new sensor is not just higher-resolution than that in the 20.1-megapixel A5000, it's a key to many of the A5100's feature upgrades as compared to that model, as we'll see in a moment.

Likely saving a little cost, it seems that Sony A5100 has switched from a vibration-based dust removal system to one based solely on an antistatic coating. By contrast, the A5000 and A6000 use piezoelectric dust-removal systems that are combined with an antistatic coating, so we'd expect them to need sensor cleaning less frequently.

Processor and performance

As in the A5000 and A6000, the Sony A5100 pairs its image sensor with a BIONZ X-branded image processor, the current generation.

According to Sony, the A5100 will shoot as many as 56 JPEG, 23 raw or 22 raw+JPEG frames at a rate of either three or six frames per second. (Buffer depths were a little better in the lab -- see our Performance page for details.) By contrast, the A5000 shoots just 27 JPEG frames at a rate of 3.5 fps or below. While the A5100 still lags the 11 fps capture of the A6000 by quite some way, it's clearly a big step forwards from the A5000 on the performance front.

Sensitivity

The same is also true of sensitivity. The Sony A5100 provides a broad sensitivity range of ISO 100 to 25,600 equivalents for still imaging, or up to ISO 12,800 equivalent for movie capture. That's the same range as provided by the more expensive A6000. By contrast, the A5000 is limited to ISO 16,000 for still capture, or ISO 3200 for movies. Unlike its more expensive sibling, though, Multi Frame Noise Reduction which captures multiple images and blends them to reduce noise while offering a boost in maximum ISO to 51,200 equivalent is not available on the A5100.

Hybrid autofocus

Perhaps the most important single difference between the A5000 and this camera, though, is on the autofocus front. That's because the Sony A5100 inherits the excellent hybrid autofocus system of the A6000, intact.

As with that camera, the A5100 sports 179 phase-detection autofocus points on its image sensor, which it combines with a 25-point contrast-detection AF system to provide what Sony calls Fast Hybrid autofocus. The A5000 has only the 25-point CDAF system, with no phase-detection capability. That means you can expect significantly greater autofocus performance for your money from the A5100 -- which is big news whether you're shooting sports, or just the kids running around.

Taking advantage of the A5100's better AF performance, it also offers an automatically-switching AF-A mode that chooses between single and continuous autofocus as needed, plus Eye AF and Lock-on AF functions as seen in the Sony A7 and A7R, and a Flexible Spot AF area function.

Video is better, too

Another important difference from the A5000 is that the Sony A5100 has significantly improved video capabilities -- and not just the fact that it sports fast hybrid autofocus with tracking, although that helps. In fact, in one respect the A5100 outperforms even the A6000: the ability to record two video file formats at once.

You might wonder why you'd want to do this, but if you stop to think about it, the idea makes a lot of sense. Although most of us want to maximize image quality at the expense of file size -- so that when we get home, we can edit to our heart's content -- the huge file-sizes that we're recording are completely useless when it comes to spontaneous, online sharing. By recording both MPEG-4 HD video for sharing and either XAVC S or AVCHD Full HD video for posterity, the A5100 can cater to both needs. It's genius, really.

And yes, we did say XAVC S. The Sony A5100 is also relatively unusual in providing for the newer, less-compressed video format, which can potentially reduce artifacts in your videos at the expense of file size. You have a choice of Full HD (1,920 x 1,080 pixel) capture at 24, 30, or 60 frames per second with 50Mbps XAVC S compression, as well as a variety of resolution / frame rate options for AVCHD and MPEG-4 capture. (Note that firmware version 2.0 adds XAVC S support to the Sony A6000. See the A6000 firmware download page for details.)

One more piece of good news: The Sony A5100 will read out the full image sensor before downsampling to your output resolution in-camera, unlike most cameras which perform line-skipping prior to readout. That means less artifacts and better image quality. Also, you can control autofocus drive speed and tracking duration for movie capture, handy given the uprated autofocus system.

LCD monitor (but no viewfinder)

One of the key differences between the Sony A5100 and A6000 is that this camera lacks a viewfinder. If you want the experience of shooting with the camera to your eye, you'll want to spend the extra for that model instead, but for those who've grown up shooting at arm's length -- or just want the smallest possible camera body -- the A5100 will prove a better option.

What you do have is a 3.0-inch, flip-up LCD monitor, just as in the A5000. Unlike that camera, though, the Sony A5100 sports a Sony WhiteMagic-branded panel that supplements the red, green and blue subpixels of most LCDs with an extra, white subpixel. The four dot per pixel arrangement allows a brighter display for better visibility when outdoors, but a lower backlight level (and thus better power consumption) when indoors. It also helps boost dot count to 921,600 dots, versus the 460,800 dots of the Sony A5000. Also unlike the A5000 and A6000, the A5100's LCD has a capacitive touch panel overlay. (The NEX-5T also has a touch panel, but it's the less responsive resistive or pressure-sensitive type.)

Slightly less battery life

Almost certainly due to the increase in sensor resolution -- and the increased processing power needed to offload more data faster than before -- the Sony A5100 has slightly lesser battery life than the lower-res A5000. (Which makes the switch to a more efficient LCD even better news, as the decrease would likely have been more significant were the old design retained.)

The Sony A5100 uses the exact same NP-FW50 lithium-ion rechargeable battery packs as the A5000, perhaps not surprisingly given its near-identical body. Sony rates the A5100 as good for 400 shots on a charge, to CIPA testing standards with 50% flash usage. That's still pretty close to the 420 shot rating of the A5000.

Internal flash

We've mentioned it in passing already, but like the A5000 before it, the Sony A5100 has a popup flash directly above the lens barrel. It has a guide number of four meters at ISO 100, the same as that of the A5100 and two meters lower than the built-in flash strobe of the A6000. Maximum sync speed is 1/160s. And as did the A5000, the Sony A5100 lacks a flash hot shoe, making its internal strobe all the more important.

Exposure

Still, many photographers choosing a mirrorless camera do so for their smaller size than an SLR -- and if size is important, you're likely not carrying an external strobe anyway. Given its generous ISO sensitivity range and generous range of exposure controls, the internal strobe will probably work out just fine for much of your shooting.

The Sony A5100 offers shutter speeds from 1/4,000 to 30 seconds and determines exposures with a 1,200-zone evaluative metering system that provides center-weighted and spot options, just like the A6000. And it provides all the exposure modes you'd expect at this price point, plus some features you probably wouldn't dare hope for.

Program, priority and manual exposure are all there, alongside consumer-friendly Intelligent Auto and Superior Auto modes, plus nice scene modes. There's also a sweep panorama function, the ability to bracket exposures across three shots, and both focus peaking and zebra functions. Of course, you can shoot in raw or JPEG file formats, and you can also customize five of the A5100's controls to your own personal tastes.

Share and shoot through your phone

And like the A5000 before it, the Sony A5100 provides in-camera Wi-Fi wireless networking connectivity, along with Near-Field Communications for quick setup with many Android phones and tablets. (Apple's iPhones and iPads still haven't shown up to the party, preferring their own proprietary alternatives to NFC.)

Not only can you offload images and movies via Wi-Fi for sharing on social networks from your phone or tablet, you can also control the A5100 remotely from your smart device. And support for Sony's PlayMemories Camera Apps -- some free, others an optional, paid extra -- is also available.

Wired connectivity

Of course, the usual HDMI high-definition video output and USB 2.0 High Speed data connection are also available, if you prefer to stick with a physical cable. Unusually for this class, the A5100's HDMI port is capable outputting uncompressed 8-bit 4:2:2 clean video files to an external recording device. The USB connection is also used to recharge the camera's battery, with the provided AC-UB10 USB charger, and is compatible with Sony's new RM-SPR1 Remote Commander wired release.

Storage

Like the A5000 and A6000 before it, the Sony A5100 stores images and movies on either Secure Digital cards, or Sony's proprietary Memory Stick Duo cards. SD card support includes both high-capacity SDHC / SDXC cards, as well as high-speed UHS-I cards.