Performance

A quick look at the spec sheet should leave no doubt that Samsung intends the NX1 to be a performance-oriented camera. With headline features such as 205 phase detect AF points (including 90% viewfinder coverage) and 15 fps continuous shooting Samsung has set high expectations. On paper it outperforms everything else in the APS-C market, though its closest competitor in terms of performance is the Canon 7D Mark II, a camera with a very fast AF system but which only shoots 10 fps.

Continuous Shooting and Buffering

The NX1 is able to shoot at burst rates of 15 fps. If you haven't used a camera that shoots this rapidly it's surprising how many frames you can rack up in short order. In fact, in some cases we actually found it to be a little bit too fast. After all, every frame you shoot is a frame you have to sort through later on. Fortunately, it's possible to set the burst rate to 8, 10, and 12 fps if desired.

Timing
JPEG Fine
RAW
RAW+JPEG Fine
Frame rate 15.5 fps 15.5 fps 15.5 fps
Number of frames 73 20 20
Buffer full rate 6.5 1.9 1.4
Write complete 8 sec 10 sec 10 sec

All timings performed using a 64GB SanDisk Extreme Pro UHS-I SDHC card (280MB/s) card.

To put this shooting speed into perspective, consider that video is often shot at 24 fps. Even when shooting 4K video, you're still only capturing 8MP individual frames. The fact that the NX1 is capturing 28MP frames at 15 fps gives you some idea of how much processing is going on under the hood.

Autofocus

DSLR-class cameras (a category into which the NX1 comfortably fits, despite its mirrorless underpinnings) have historically excelled at distance tracking thanks to their reliance on phase detect autofocus. Mirrorless cameras, on the other hand, have benefited from focusing directly off the sensor, affording them higher accuracy as well as allowing for image processing algorithms to work off the image sensor to identify and track subjects.

The NX1 isn't the first camera to include a hybrid autofocus system, however it may be the most aggressive such system to date. It incorporates 205 phase detect and 209 contrast detect AF points, and camera and lens exchange data at a rate of 240 fps. On top of that, the NX1 includes some significant computing power to process all that data. In theory, it should be able to generate reliable depth information while understanding the image well enough to follow a subject. Let's see how it works.

Depth Tracking

We generally expect DSLRs to perform well on this type of testing, though our expectations for mirrorless cameras are typically a bit lower based on historical experience. Samsung has positioned the NX1 as a serious DSLR competitor - one that might be used for action or sports shooting - so it needs to excel in this area, especially if it wants to go head to head with competitors such as the Canon 7D Mark II.

We provided a brief preview of the NX1's autofocus in our Shooter's Experience in which we photographed our editor, Richard, doing fast sprints on his bike. Below is a full sequence of 15 photos – a 1 second burst – made during that shoot using the Samsung 50-150mm F2.8 S lens.

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15

This is a series of 15 shots a (one second burst). We had Multi-AF mode selected, so the camera tracked Richard with a cloud of AF points that covered his body and the bike. The camera kept him in focus, though there are minor differences in terms of where the camera focused on him between frames. Manually selecting an single AF point would have given us more precision. (Samsung 50-150mm F2.8 S at F2.8)

Most of the photos in the sequence are either in focus or close to it. Several repetitions of this test provided fairly consistent results. As a point of comparison, we also shot Richard using a Canon 7D Mark II with a Canon 70-200mm F2.8 L lens at 10 fps. As we expected, the Canon did very well on this test, but not really any better than the NX1. Both cameras landed most of the shots in focus.

This test is consistent with our overall experience with the NX1: depth tracking is very good, as long as you have enough light (more on this later).

Subject Tracking

Where the NX1 has the potential to do something really special is to combine DSLR-class autofocus with the level of subject tracking typically associated with on-sensor focus, and for the most part it does a very good job.

When shooting in Multi-AF mode (e.g. the camera is free to use all AF points) and with continuous autofocus enabled, the NX1 will automatically attempt to track a subject once focus is acquired. This can be accomplished either by letting the camera choose the initial AF area or by starting with a user defined AF area. In either case, as soon as focus is achieved, a flurry of AF points will appear over the the subject and will attempt to track it as long as it stays in frame.

When given a well isolated subject such as this soccer player the camera does a good job at tracking the subject as it moves around the frame. However, when multiple players were present the camera had a tendency to jump around between subjects at times.

Processed in Adobe Camera Raw (exposure +2.15, highlights -30).

In practice the system actually works quite well, though not without some frustrations. As one would expect, well isolated subjects are picked up and tracked fairly easily, and when combined with depth tracking the system does an impressive job.

Though based on entirely different technologies, we found the NX1's subject tracking consistently better than Canon's iTR technology in the 7D Mark II. Where the 7D II would often struggle to keep up with (and often lose) a subject, the NX1 felt more responsive and left us with a higher level of confidence that it was tracking the subject. The NX1 doesn't quite reach the levels of speed and accuracy of subject tracking Nikon's 3D tracking realizes, but few implementations do, and the Samsung performs quite respectably here as you can see in our video demonstration below:

This video shows an example of subject tracking on the NX1. Notice that the system seems to remember what subject you focused on initially - even if you move in or out causing other parts of the scene to come into the DOF zone, the AF points return to the original subject when the DOF zone narrows.

That's not to say that the NX1's subject tracking is without its faults. The AF points can sometimes jump off a well-isolated subject and lock onto something elsewhere in the frame, and in low light the system begins to struggle with tracking in general. It works, but don't expect miracles.

One thing that takes some getting used to is the sheer number of AF points that light up at one time. We've seen up to 35 AF points light up over a subject, some of which may appear at the fringes or even beyond the edge of the subject entirely. It might best be described as a "shotgun" approach to focusing: you know that in totality, the subject you're trying to follow will be in focus, but you're frequently not sure what part of it will be in focus.

The NX1 will use up to 35 focus points to focus on and track a subject. There aren't many cases where it actually uses 35 points, but it's not uncommon for 10-15 points to light up at once. (We had to find an example like this tree to get the full 35 points to light up.)

It's a contrast to a system like Nikon's 3D tracking which commits to one or two AF points that diligently follow a subject around. That said, the two systems work very differently and it's a bit of an apples to oranges comparison. Both systems work, but the experience of using them is qualitatively different. Which brings us to one of the NX1's AF modes that does rival, or even exceed, the accuracy and speed of Nikon's implementation: Tracking-AF.

Tracking-AF is activated using the rear touch screen and effectively offers a tap-to-focus mode for subject tracking. Simply tap your subject on the screen and the camera places a single box over it, from which point the camera tracks the subject as it moves around.

Tracking-AF is a more deliberate and precise approach than letting the system manage subject tracking. It feels much more "sticky" and the NX1 is very good at not losing the subject, even while panning and zooming in and out. In fact, this may be some of the best subject tracking we've seen, so it's a shame that usability for stills is limited by the fact that it only works by tapping the touchscreen. We could imagine an EVF-friendly implementation that always starts tracking from a user-selectable point (a la Nikon's implementation, or Sony's 'Lock-on AF'). For now, Tracking-AF is better suited to video and LCD operation.

AF Challenges

Overall, the NX1's autofocus system is fast and effective, however it can struggle in low light. Although we haven't been able to precisely quantify the limit at which this occurs, there's definitely a point at which AF performance drops off noticeably in real world use. The result is a lot of back and forth focus hunting or a complete failure to focus. In contrast, the Canon 7D II, which we sometimes shot alongside the NX1 for comparison, often continued to focus reliably in light levels the NX1 struggled with. This is not surprising - on-sensor phase detect uses masked pixels that we imagine receive very little light compared to the line sensors of traditional, dedicated phase-detect modules in DSLRs.

AF performance also depends on lens selection. With Samsung's newest S-series lenses, such as the 16-50mm F2.0-2.8 S and 50-150mm F2.8 S, focus is consistently fast and accurate. Performance seems notably slower on any of the older Samsung optics, sometimes seeming to revert entirely to contrast detect autofocus even in daylight. We've reached out to Samsung for clarification on this behavior and hope to provide an update.

Viewfinder

We don't usually discuss a camera's viewfinder when evaluating performance, however in the case of the NX1 the EVF materially contributes to the camera's overall performance. Notably for an EVF, the NX1's viewfinder has essentially zero lag, making it a reasonable alternative to an optical viewfinder for everyday use.

Additionally, the excellent EVF does an outstanding job of overlaying subject tracking information and updates very quickly. As a result, it's very easy not only to see what you're shooting, but how the system is tracking it in real time.