Sony A7S Performance


Timing and Performance

Generally good performance overall, but powerup is sluggish.

Startup and Play to Record

Power on
to first shot

~2.0 seconds

Time it takes to turn on and capture a shot.

Play to Record,
first shot

~0.5 second

Time until first shot is captured.

Powerup to first shot was sluggish at about 2 seconds. Switching from Play to Record mode and taking a shot was pretty fast, though, at about half a second.


Shutter Response (Lag Time)

Shutter Mode

EFC Shutter Enabled
(Default)
EFC Shutter Disabled

Comments

Full Autofocus,
Single-area AF mode

0.178 second
0.320 second

Time from fully pressing shutter button to image capture, with the lens already at the proper focal distance setting. (AF timing performed with the Sony FE 35mm f/2.8 lens.)

Full Autofocus,
Multi-area AF mode

0.183 second
0.325 second

Time from fully pressing shutter button to image capture, with the lens already at the proper focal distance setting.

Manual Focus

0.129 second
0.271 second

For most cameras, shutter lag is less in manual focus than autofocus, but usually not as fast as when the camera is "prefocused".

Prefocused

0.024 second
0.168 second

Time to capture, after half-pressing and holding shutter button.

Using Electronic First Curtain shutter which is enabled by default, the Sony A7S's autofocus speeds were very good for a CSC, and competitive with prosumer DSLRs in our static tests. The Sony A7S's full-autofocus shutter lag (with the subject at a fixed distance) was 0.178 second in Single-area AF mode. This increased slightly to 0.183 second in Multi-area AF mode. When manually focused, the Sony A7S's lag time dropped to 0.129 second, which is also very good. The Sony A7S's prefocused shutter lag time was only 24 milliseconds,which is faster than most CSCs and much faster than DSLRs.

When using the all-mechanical shutter mode by disabling Electronic First Curtain, full autofocus shutter lag was significantly slower (3rd column from the left in the table above), manual focus shutter lag was over twice as slow, and prefocused shutter lag was about 7x slower.

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.


Cycle Time (shot to shot)

Single Shot mode
Large/Extra Fine JPEG

0.53 second

Time per shot, averaged over 40 shots with no signs of slowing, 2 seconds to clear*.

Single Shot mode
RAW

0.57 second

Time per shot, averaged over 40 shots with no signs of slowing, 2 seconds to clear*.

Single Shot mode
RAW + L/F JPEG

0.52 second

Time per shot, averaged over 40 shots with no signs of slowing, 6 seconds to clear*.

Early shutter
penalty?

No

Some cameras don't snap another shot if you release and press the shutter too quickly in Single Shot mode, making "No" the preferred answer.

Continuous mode
Mech. Shutter, Large/Extra Fine JPEG

0.44 second (2.25 frames per second);
100+ frames total;
8 seconds to clear*

Time per shot, averaged over 100 shots, with no signs of slowing.

Continuous mode
Mech. Shutter,
RAW

0.44 second (2.25 frames per second);
100+ frames total;
2 seconds to clear*

Time per shot, averaged over 100 shots, with no signs of slowing.

Continuous mode
Mech. Shutter,
RAW + L/F JPEG

0.45 second (2.24 frames per second);
70 frames total;
13 seconds to clear*

Time per shot, averaged over buffer length of 70 frames, then slows to an average of 0.61s or 1.65fps when buffer is full.

Continuous mode
EFC Shutter, Large/Extra Fine JPEG

0.31 second (3.25 frames per second);
20+ frames total;
2 seconds to clear*

Time per shot, averaged over 20 shots, with no signs of slowing.

Continuous mode
EFC Shutter,
RAW

0.31 second (3.25 frames per second);
20+ frames total;
3 seconds to clear*

Time per shot, averaged over 20 shots, with no signs of slowing.

Continuous mode
EFC Shutter,
RAW + L/F JPEG

0.31 second (3.22 frames per second);
39 frames total;
13 seconds to clear*

Time per shot, averaged over buffer length of 39 frames, then slows to an average of 0.61s or 1.65fps when buffer is full.

Speed Priority
Continuous mode

Large/Extra Fine JPEG

0.20 second (4.99 frames per second);
62 frames total;
22 seconds to clear*

Time per shot, averaged over buffer length of 62 frames, then slows to an average of 0.49s or 2.05fps when buffer is full.

Speed Priority
Continuous mode

RAW

0.20 second (4.99 frames per second);
39 frames total;
8 seconds to clear*

Time per shot, averaged over buffer length of 39 frames, then slows to an average of 0.39s or 2.59fps when buffer is full.

Speed Priority
Continuous mode

RAW + L/F JPEG

0.20 second (4.99 frames per second);
28 frames total;
13 seconds to clear*

Time per shot, averaged over buffer length of 28 frames, then slows to an average of 0.60s or 1.68fps when buffer is full.

Flash Recycling

N/A

Flash at maximum output.

*Note: Buffer clearing times measured with a SanDisk Extreme Pro 95MB/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.

Single-shot cycle time was about 0.5 second when shooting Large/Extra Fine JPEGs (using default Electronic First Curtain shutter). This increased slightly to about 0.6 second when shooting RAW, but RAW+ Large/Fine JPEG cycle time returned to about 0.5 second. This is very good for a CSC, but about average compared to most DSLRs. (Note that disabling EFC does add about 0.1 second lag time to these numbers.)

Standard continuous mode performance was quite slow at about 2.3 frames per second when using the all mechanical shutter mode. When leaving Electronic First Curtain enabled, continuous mode increased to about 3.2 frames per second (and we got similar speeds in Silent Shooting mode, which uses an all-electronic shutter).

Speed Priority Continuous mode managed about 5 frames per second, though autofocus is fixed at the first frame of a burst in this mode. (Unlike the Sony A7, the A7S does not have on-chip phase-detect AF pixels, so continuous autofocus is not supported in Speed Priority mode.)

Buffer depths were excellent, ranging from no limit in standard continuous mode when shooting Extra Fine JPEGs, to 62 Extra Fine JPEGs in Speed Priority mode, to a worst case of 28 RAW+JPEG frames in Speed Priority mode. Note, though, that our target for this test was designed to be difficult to compress, so maximum burst lengths should be even longer with typical subjects.

Buffer clearing times were pretty good, but can get a bit lengthy when shooting in Speed Priority mode, especially when shooting Extra Fine JPEGs (note that the A7S cannot shoot Extra Fine JPEGs together with RAW files, falling back to Fine quality when shooting in RAW+JPEG mode).

Bottom line, apart from sluggish power-on to first shot, the Sony A7S's performance is quite good compared to most mirrorless cameras, especially when considering the large full-frame sensor. Some may have expected that perhaps the A7S's lower resolution would allow for a faster burst mode than the A7, but that didn't turn out to be the case. Somewhat surprisingly though, autofocus tested noticeably faster than its higher-resolution sibling, the Sony A7, even though the latter has on-chip phase-detect pixels. (The Sony A7 is however able to continuously autofocus at the highest frame rate while the A7S cannot.)

Battery Life

Decent battery life for a Compact System Camera.

Operating Mode Battery Life
Still Capture,
(CIPA standard, LCD Monitor)
380 shots
Still Capture,
(CIPA standard, EVF)
320 shots

The Sony A7S uses a custom NP-FW50 rechargeable lithium-ion battery pack for power, and comes with two batteries, a dedicated charger and an AC adapter for in-camera charging via USB. The battery is rated for 380 shots per charge when using the LCD monitor and 320 shots when using the electronic viewfinder, according to the CIPA standard. Battery life is pretty good for a full-frame mirrorless camera, but poor compared to most DSLRs. An optional VG-C1EM vertical grip is available which doubles battery life with two batteries.

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))

 



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