Nikon D4S Performance

Generally excellent speed for a pro DSLR.

Startup and switching from Play to Record mode and taking a shot were both very fast, almost instantaneous. Buffer clearing time depends on the image size and quality, burst length and the speed of memory card used, but was generally very good with a 100MB/s CompactFlash card considering the deep buffers.

In terms of the Nikon D4S's ability to determine that it's properly focused when shooting the same target multiple times (with no change of focus setting between iteration, to remove the impact of lens AF speed), its speed was good, but unimpressive for a professional model. The D4S required 0.204 second using single-area center AF mode, and 51-point Auto Area AF lag measured 0.288 second. Some consumer DSLRs are actually faster in this metric, but keep in mind this test does not actually include slewing focus on the lens, nor does it reveal the D4S' focus tracking capability, which is far better than any consumer DSLR (we have no way to objectively test that in the lab, though).

In manual focus mode shutter lag was extremely fast, at only 44 milliseconds. We measured just slightly faster for prefocused, at 43 milliseconds. These times are very fast, but some mirrorless models with electronic first curtain options are actually faster.

As expected, the Nikon D4S's Live View mode adds considerable AF shutter lag. We measured 0.914 second for full autofocus which is pretty sluggish, though faster than previous models (however the lens used will have a large impact on focus speed with contrast-detect AF).

Once prefocused, shutter lag in Live View mode was 0.239 second, which is pretty good but still quite a bit slower than using the optical viewfinder.

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 time performance was excellent for a pro DSLR model, at 0.29 second per frame for large/fine JPEGs (Optimal Quality setting), 0.36 second for 14-bit RAW (Lossless Compressed), and 0.33 second for RAW+ L/F Optimal JPEGs.

Continuous Hi-speed mode was very fast. We measured between 10.6 and 10.8 frames per second depending on the file type, just a little slower than Nikon's 11 fps spec. Note, though, that unlike the D4, AF and AE are not locked from the first frame in a burst on the D4S at this speed.

Buffer depths were excellent, with a programmable limit of up to 200 shots per burst. While we didn't keep testing to see what the buffer limits were for just JPEG or RAW files, with lossless compressed RAW + best quality JPEG frames, we managed 43 frames before the camera began to slow with a 100MB/s CompactFlash card, and you're likely to do even better as our test target is designed to be difficult to compress.

Buffer clearing is fast, but can be a little lengthy with such deep buffers. We measured up to 19 seconds after the maximum length RAW + JPEG burst with our 100MB/s CompactFlash card.

Buffer depths and clearing times may improve with an XQD card, however we did not repeat our tests with one.

USB 2.0 download speeds were pretty fast.

Bottom line, the Nikon D4S is extremely fast in most respects, with very fast frame rates, deep buffers for long bursts, and very low shutter lag. AF-S speed was slower than average for a professional model in our lab, though. Keep in mind however that our AF tests are with static subjects, and we have no way of objectively testing the D4S's autofocus acquisition and tracking performance with real-world subjects in the lab. As with prior Nikon pro models, though, even with slower-than-average AF-S lab test results for its class, the D4S's autofocus performance in the real world with moving subjects is excellent.

Battery Life

Excellent battery life for a professional SLR.

The Nikon D4S uses a custom rechargeable lithium-ion battery pack for power, and comes with both a single battery and charger. The CIPA rated 3,020 shots per charge using the optical viewfinder is excellent for a pro SLR, but keep in mind the D4S does not have a built-in flash which is normally fired for 50% of shots when tested using the CIPA standard. Unfortunately, Nikon does not seem to publish battery life for Live View mode, but it's a safe bet that it's considerably shorter.

The table above shows the number of shots the camera is capable of on fully-charged 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))