Sony A5100 Performance

Generally good performance, though startup is sluggish.

The Sony A5100's startup time (power on to first shot) was slower than most CSCs, and much slower than most DSLRs. Switching from Play to Record mode and taking a shot was reasonably fast, though.

The Sony A5100's full-autofocus shutter lag (with the subject at a fixed distance) was about 0.24 second in Single-area (Center) AF mode and 0.23 second in Multi-area (Wide) AF mode, with the 16-50mm kit lens at a medium focal length. That's a little faster than the NEX-6 tested (~0.26s) and on par with most consumer DSLRs, though not as fast as the Sony A6000's 0.15 second result.

Enabling the flash added a small delay for preflash metering, increasing lag to about 0.352s. When manually focused, the Sony A5100's shutter lag was about 0.13s, which is pretty good, though not as fast as some competitors. The A5100's prefocused shutter lag was only 21 milliseconds, much faster than most CSCs and faster than any DSLR -- we have the camera's lack of a mirror and electronic front curtain shutter (which can't be disabled) to thank for that.

To minimize the effect of different lens' focusing speed, we test AF-active shutter lag with the lens already set to the correct focal distance.

Single-shot cycle times were very good for a mirrorless ILC camera, at 0.55 second for large/fine JPEGs, 0.59 second for RAW files and 0.56 second for RAW+JPEG frames.

Continuous Hi burst mode performance was about average for a mirrorless camera these days, at just over 6 frames per second regardless of file type, meeting Sony's 6 fps specification. And thanks to the A5100's Hybrid AF, continuous autofocus is available at this speed. There is also a Continuous Lo (3 fps) setting, however we did not test that option.

Buffer depth for large/fine JPEGs in Continuous Hi mode was also excellent, at 67 frames before the camera slowed. Note that our test target for this was designed to be difficult to compress, so burst lengths should be longer with typical subjects. When shooting RAW files, buffer depth dropped to 25 frames, and to 23 frames with RAW+L/F JPEG files, which is still quite generous for its class. Buffer clearing after max-length bursts took some time even with a fast UHS-I SD card, though, ranging between 15 seconds after a max-length burst of RAW files, to 21 seconds after a burst of large/fine JPEGs.

The built-in flash was able to recycle from a full discharge in 2.2 seconds on average, which is fast.

Bottom line, the Sony A5100's performance was generally quite good for its class in our tests, with fast AF speeds, extremely quick prefocused shutter lag and a 6 fps burst mode that supports continuous autofocus. Startup time was sluggish, though, and while buffer depths were quite good, clearing after a max-length burst of 24-megapixel images can take some time even with a fast UHS-I SD card.

Battery Life
Good battery life for a Compact System Camera.

The Sony A5100 uses a custom NP-FW50 rechargeable lithium-ion battery pack for power, and comes with both a single battery and an AC adapter for charging in-camera via USB. CIPA-rated battery life is above average for a mirrorless camera, at 400 shots. As is usually the case, though, we recommend getting a second battery for your A5100 if you plan any extended outings.

The table above shows the number of shots the camera is capable of (on a fully-charged rechargeable battery), based on CIPA battery-life and/or manufacturer standard test conditions.

(Interested readers can find an English translation of the CIPA DC-002 standards document here. (180K PDF document))