Sony A77 Performance

Camera Reviews / Sony Cameras / Sony Alpha i Full Review

Navigate Review Jump to review page...

Sony A77 Performance

Note: The following performance data has been updated after upgrading to v1.06 firmware.

Timing and Performance

Excellent autofocus and burst speeds, but some sluggish mode switching.

Startup/Shutdown
Power on to first shot	~0.8 second	Time it takes to turn on and capture a shot.
Shutdown	~1.0 second	How long it takes camera to turn off before you can remove the memory card.
Buffer clearing time	7 seconds after 19 large/extra fine JPEGs*	Worst case buffer clearing time. -- This is the delay after a set of shots before you can remove the card.
	12 seconds after 15 RAW files*
	13 seconds after 13 RAW+ L/EF JPEG files*
*Note: Buffer clearing times measured with a Sony SF-32UX 94MB/sec UHS-I SDHC card. Slower cards will produce correspondingly slower clearing times. Slow cards may also limit length of bursts in continuous mode. ISO sensitivity and noise reduction settings can also affect cycle times and burst mode performance.

Startup and shutdown times are a bit slower than typical SLRs, but much improved over older firmware versions. (These results were measured using v1.06 firmware.) Buffer clearing times were reasonable given the size of files and buffer when using a very fast card. (We used a fast "up to 94MB/s" UHS-I compliant Sony SDHC card.)

Mode Switching
Play to Record, first shot	~1.0 second	Time until first shot is captured.
Record to Play	~1.7 seconds	Time to display a large/extra fine JPEG file immediately after capture.
Display recorded image	~0.5 second	Time to display a large/extra fine JPEG file already on the memory card.

Mode switching performance was a bit sluggish, though displaying a previously captured image was pretty fast.

Shutter Response (Lag Time)
Full Autofocus Single Area (center) AF	0.124 second	Time from fully pressing shutter button to image capture. (All timing measurements made with a Sigma 70mm f/2.8 lens)
Full Autofocus Wide Area AF	0.119 second	Time from fully pressing shutter button to image capture.
Full Autofocus, Single-area AF mode Auto Flash Enabled	0.326 second	Time from fully pressing shutter button to image capture, with the lens already at the proper focal distance setting, Auto flash enabled.
Continuous AF	0.122 second	This mode usually shows no speed increase with our static subject; we have no way to measure performance with moving subjects.
Manual focus	0.085 second	For most cameras, shutter lag is less in manual focus than autofocus, but usually not as fast as when the camera is "pre-focused."
Pre-focused	0.054 second	Time to capture, after half-pressing and holding shutter button. (Electronic first curtain shutter enabled.)

Looking at the Sony A77's ability to determine that it's properly focused when shooting the same target multiple times, its autofocus speed is very good. The SLT-A77 required only 0.124 second for full AF using the center focus point. This decreased slightly to 0.119 second in wide-area AF mode. With the flash enabled, the A77's full AF shutter lag increased to 0.326s, to account for the preflash metering, which is still pretty fast.

Continuous autofocus mode lag time was 0.122 second, and manual focus was even faster at about 0.085 second. When prefocused, shutter lag was 0.054 second which is very good for an enthusiast model, though not as fast as the fastest professional SLRs we've tested, nor as fast as the latest Sony NEX models. (The Nikon D3S tested at 0.043s while the Canon 1D Mark IV tested at 0.049s. The NEX-5N and NEX-7 both managed 0.022s with their electronic first curtain shutters.) These timing results are with the Sony A77's electronic first curtain shutter active, which is the default setting.

Cycle Time (shot-to-shot)
Single Shot mode Large Extra Fine JPEG	0.42 second	Time per shot, averaged over 12 shots, 6 seconds to clear.
Single Shot mode RAW	0.42 second	Time per shot, averaged over 5 shots. 5 seconds to clear.
Single Shot mode RAW + L/F JPEG	0.42 second	Time per shot, averaged over 4 shots, 6 seconds to clear.
Early shutter penalty?	No	Some cameras refuse to snap another shot if you release and press the shutter too quickly in Single Shot mode, making "No" the preferred answer.
Continuous mode Large Extra Fine JPEG	0.13 second (8.00 frames per second); 19 frames total; 7 seconds to clear*	Time per shot, averaged over buffer depth of 13 shots, then slowed to an average of 0.88 seconds, or 1.14 fps.
Continuous mode RAW	0.13 second (7.95 frames per second); 15 frames total; 12 seconds to clear*	Time per shot, averaged over buffer depth of 15 shots, then slowed to an average of 0.85 seconds, or 1.18 fps.
Continuous mode RAW + L/F JPEG	0.13 second (7.95 frames per second); 13 frames total; 13 seconds to clear*	Time per shot, averaged over buffer depth of 13 shots, then slowed to an average of 1.29 seconds, or 0.78 fps.
Continuous Advance Priority AE mode L/F JPEG	0.09 second (11.61 frames per second); 17 frames total; 7 seconds to clear*	Time per shot, averaged over buffer depth of 17 shots, then slowed to an average of 0.96 seconds, or 1.04 fps.
Flash Recycling	3.2 seconds	Flash at maximum output.
*Note: Buffer depths and clearing times measured with a Sony SF-32UX 94MB/sec UHS-I SDHC memory card. Slower cards will produce correspondingly slower clearing times. Slow cards may also limit length of bursts in continuous mode. ISO sensitivity and other settings such as DRO or NR can also affect cycle times and burst mode performance.

Shot-to-shot cycle times were good for an SLR-class camera, at about 0.42 second no matter the file type. Continuous mode speeds were excellent, especially for the extreme resolution, at about 8 frames-per-second in standard continuous mode. Continuous Advance Priority AE mode was faster than any SLR we've tested at full resolution, at 11.61 frames-per-second for large/extra fine JPEGs. In this mode, aperture is fixed at f/3.5 or the maximum aperture of the lens, whichever is smaller, and exposure is based on the first frame of a burst. Still, truly remarkable for a 24.3-megapixel camera.

Buffer depths were good for the size of files, ranging from 13 to 19 frames per burst before slowing down in our tests. You should be able to do better with typical subjects when shooting JPEGs (our target for this test is designed to be difficult to compress).

Buffer clearing was reasonable with our fast "up to 94MB/s" Sony UHS-I compliant SDHC card, at 7 seconds after a maximum-length large/extra fine JPEG burst, 12 seconds after a RAW burst, 13 seconds after RAW + large/fine JPEG burst, and 7 seconds after a Continuous Advance Priority AE burst of large/fine JPEGs.

The flash was able to recycle from a full discharge in 3.2 seconds, which is good.

Download Speed
Windows Computer, USB 2.0	14,534 KBytes/sec	Typical Values: Less than 600=USB 1.1; 600-769=USB 2.0 Low; Above 770=USB 2.0 High

Download speeds were very fast, quick enough that you won't feel the need for a separate card reader, even with large memory cards. (Note that this test was performed with a Sony SF-32UX 94MB/sec UHS-I SDHC card: Slower cards would likely show slower transfer times.)

Bottom line, the Sony Alpha SLT-A77's autofocus and shutter lag are excellent, while burst performance is remarkable. Buffer depths are good for its class given the huge files, but you'll want to get the fastest memory card you can afford to minimize buffer clearing times. Some mode switching times are a bit sluggish, but overall performance is quite fast making the Sony A77 suitable for all types of shooting, including sports.

Battery

Battery Life
Good battery life for an interchangeable lens camera with EVF, but below average compared to a traditional SLR with optical viewfinder.

Operating Mode	Number of Shots
Electronic Viewfinder, (CIPA standard)	470
Live View LCD, (CIPA standard)	530

The Sony A77 uses a custom rechargeable NP-FM500H lithium-ion battery for power, and ships with a charger. Battery life is a below average compared to an SLR using an optical viewfinder, but pretty good for one equipped with an electronic viewfinder. We recommend you pick up a spare battery and keep it freshly charged and on-hand for extended outings or shooting video. Sony also offers an optional VG-C77AM vertical grip that can house up to two NP-FM500H battery packs which increases battery life to 1,000 shots with the LCD monitor.

The table above shows the number of shots the camera is capable of (on either a fresh set of disposable batteries or a fully-charged rechargeable battery as appropriate), 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))