Saturday, August 27, 2011

Sony NEX-FS100 review


We've been uncommonly keen to get our hands on the Sony NEX-FS100 ever since we first heard about it back in March. You see, this is no ordinary camcorder. Its spec sheet reads like a liturgy of filmmakers' prayers: a large Super 35mm Exmor CMOS sensor, interchangeable lenses, XLR inputs and proper, professional controls. Sure, it comes with a $6,600 price tag to match, but it also heralds a trend that should ultimately benefit pros and ordinary gadget denizens alike: the arrival of big, bold DSLR-style optics within dedicated camcorders. How do these optics effect the quality of the NEX-FS100's footage? Plant yourself somewhere comfortable and click past the break to find out.



The sensor

There's only one way to begin a review of the NEX-FS100 and that's with the words "Super 35mm," which are emblazoned across the camera's packaging, the device itself and all Sony's promotional literature. The Super 35mm Exmor CMOS sensor really does make this camera unique amongst its competitors -- that's why Sony's marketing people seized on it, and it's also why we'll focus on this one spec at the expense of more niche features like slow-mo, GPS or picture profiles. To put it bluntly, were it not for the sensor, we wouldn't bother reviewing this camera at all.


The NEX-FS100 enters a market where average sensor sizes are woefully small, not only in comparison to full-frame or APS-C DSLRs, but also compared with those hefty 35mm celluloid cameras that still whir away on most Hollywood shoots and set a global benchmark for cinematic beauty. Digital filmmakers have been crying out for bigger sensors for years, mainly because they allow you to shoot aesthetically pleasing footage with shallow depth of field. In contrast, a small sensor tends to bring more into focus and hence make a picture look flat -- in other words, typical video. Another key advantage of a big sensor is low-light performance, because pixels spread out over a larger area can be made more sensitive without introducing noise.


So, exactly how big is the NEX-FS100's Super 35mm sensor? Well, if you thought the '35mm' label described a full-frame sensor of the type you'd find in a high-end DSLR like the Canon 5d, then you're going to feel seriously let down. What's more, if you thought the 'Super' referred to something even bigger than full-frame, then you'll be even more bitterly disappointed. Sticking with SLR lingo for a minute, the NEX-FS100 could more accurately be described as "almost APS-C." Despite all the marketing hype, its 23.6mm by 13.3mm sensor is actually slightly smaller than most consumer DSLRs on the market. It's also out-done by the CMOS in the NEX-VG10 (and the coming VG-20), which timidly began Sony's large sensor revolution a year ago and costs a fraction of the price of the FS100.

The marketing blurb will try to convince you that S35 works out better than a full-frame DSLR once you take into account 16:9 cropping and so-called line-skipping (which is how extremely hi-res DSLRs output lowly 1080p), but none of this negates the fact that a 'true' 35mm sensor has a bigger effective surface area and hence more oomph than Sony's S35 format when it comes to of depth-of-field control and low-light performance.


Ready to dismiss the NEX-FS100 as falsely described goods? Feel like grabbing your tripod and heading home? Please, hold your horses for just one second. First of all, the Super 35mm moniker isn't a complete fabrication: it relates to a real format, albeit one from the world of celluloid filmmaking. In a movie camera, 35mm film runs vertically past the image frame, rather than horizontally as it does in a celluloid stills camera. This means that the 24mm height of a stills frame becomes the width of the movie frame, resulting in a much smaller frame area. The word "Super" relates to a popular modification of 35mm which slightly increases the area of the frame by encroaching on a section of the film strip previously reserved for the movie's soundtrack. One could argue that Sony's marketing people have been disingenuous in their (over-)use of the Super 35mm label, particularly when many among their target audience won't be familiar with celluloid terminology. Ultimately, however, Sony is telling the truth about its sensor.

The fact is this: the sensor in the NEX-FS100 is still enormous compared to virtually every one of its rivals under $10,000. Leaving aside the NEX-VG10, which lacks professional credentials, the closest competition to the FS100 comes from the Panasonic AG-AF100, which has a Micro Four Thirds sensor that covers just 65 percent of the area of Super 35mm. Meanwhile, the ⅓-inch sensor in the Canon XF305 covers just five percent of Super 35mm. As a final comparison, most well-regarded consumer camcorders tend to have quarter-inch sensors, which would cover just two percent of a Super 35mm frame.


E-Mount Lens and optical controls

The NEX-FS100 can be bought without a lens for around $5,900 or with a 18-200mm E-mount optically stabilized F3.5 lens for $6,600. Our review sample came with this kit lens, which was justokay. It was sharp at the majority of focal lengths, the auto focus was quiet and reasonably speedy and the lens was light and easy to pack. But it was a slow lens with a relatively small maximum aperture that inevitably cancelled out some of the positive effects of the large sensor. It wasn't particularly well-built either, with moving sections that seemed vulnerable to dirt accumulation and that also seemed slightly loosely fitted together -- although this didn't turn out to be a hindrance during our test shoots. In the real-world, the kit lens just about gets the job done.


This leads us on nicely to the camera's E-mount system, which in any case frees you up from dependence on the kit lens, and which is an increasingly sensible choice as a lens platform. With third-party manufacturers also making E-mount lenses, there are already some of super-fast prime lenses on the market and the choice will only increase over time. Another consideration is that any E-mount lenses you invest in will also work with any other NEX cameras you might add to your arsenal, including the NEX-VG10 as a backup camera and the wonderful NEX-C3 to handle stills. Finally, there's also the potential to add A-series and Minolta lenses via the LA-EA1 adapter that retains AE and slow AF, as well as other adapters that totally lose automatic controls. The imminent LA-EA2 adapter, which sports a translucent mirror, should improve matters further. In other words, the E-mount system delivers all the choice and flexibility you should need.


There's one thing the NEX-FS100 won't do, however, and that's auto zoom. No matter what kind of stuff you shoot, you'll miss this facility and you'll probably have to adjust your shooting style to compensate. As you'll see in the daylight sample footage below, there are a number of messy crash zooms, resulting from the fact that we generally prefer to zoom in or out quickly, but there's no way to do this neatly with the manual zoom ring. Long, smooth zooms will be even harder to pull off consistently unless you're on a tripod, because the hand that turns the ring is the same hand that stabilizes the front part of the camera when you're going handheld.


Another important omission is built-in neutral density filters. These would have been very handy in our daylight shoot, as they would have allowed us to open up the aperture further and gain more control over depth-of-field. But instead, Sony has made the kit stop right down to F40 -- so you can get properly exposed footage in bright sunshine, but at the expense of selective focus. So, the only way to shoot outdoors and benefit fully from the large sensor will be to bring your own ND filters, matte box and possibly a rail system to support it all properly. Some people will feel perfectly at home with such accouterments, but others -- especially from the worlds of news and documentaries, will see it as unnecessarily cumbersome.



Body, layout and build quality

The NEX-FS100 has a smart modular design that makes it by far the most portable and flexible pro camcorder we've ever used. With the lens, grip and viewfinder detached, the body weighs just 1.04kg (two pounds four ounces) and is easily small enough to pack away in a DSLR bag with plenty of space left in the side-sections and pockets for the other components. By comparison, non-interchangeable lens camcorders, like Sony's popular Z series, have been extremely difficult to pack in anything other than a large, dedicated and conspicuous camera bag. This will be extremely important to one key market segment: the lone shooter who needs to travel as lightly as possible. The modular design also means there are lots of extra tripod mounts around the camera. For example, the hand-grip screws into a mount on the side which could alternatively be used to shoot in portrait mode on a tripod -- not something that will be used a lot, but flexibility like that always comes in handy at some point.


Of course, the argument will arise: why not just shoot on a DSLR, which would be even more portable? We might as well tackle this issue right now, because it's the body and layout of the NEX-FS100, rather than just the lens and sensor, that make it a more serious professional contender than any DSLR currently on the market. Yes, filming on a good DSLR like the Nikon D5100 or the Canon 7D is an increasingly viable option. But you really need a video camera that can shoot all day without getting hot and switching itself off -- and the NEX-FS100 meets that basic requirement easily with a stated maximum recording time of 510 minutes. It also has the option of a 128GB Flash Memory Unit, which costs around $1000 extra and stores ten hours of footage. We had the luxury of an FMU during our test shoots, but we also used high quality 16GB SDHC cards that stored over an hour of full quality footage with no problems.


Good video demands that you can see what you're shooting, and the NEX-FS100 covers that base with a wonderful 3.5-inch LCD and separate viewfinder attachment for outdoor shooting that is far more effective than any DSLR screen. There are a few niggles in this area, including the LCD's susceptibility to finger smudges that are very difficult to wipe off, and also the fact that it doesn't flip out to the side, which means you can't tilt it downwards when shooting with the camera above your head. However, the camcorder sports an HDMI output and so cries out for a good field monitor, which would remove all these limitations.


The NEX-FS100 has two XLR inputs, one on either side, which are essential for using broadcast-quality boom mics and radio mics. With a DSLR, or even with the NEX-VG10, you'd end up having to buy a separate audio adapter or recorder like the Zoom H4N and that would mean a lot of extra stuff to think about on a shoot, including an extra device to mount on the tripod, an extra 'record' button to push, and even clapper boards and scene announcements to help match up audio and video in post production.


Crucially, the NEX-FS100 has hardware buttons and switches for all the controls you tend to need when shooting video, including quick-auto buttons for exposure and focus (while still shooting in manual mode), expanded focus, auto and manual lock, white balance set and presets, gain, audio levels and audio channel directions. Only settings that generally need to be configured once per shoot (or less) are relegated to the menu system, which is accessed via the touchscreen and is clunky but effective. In contrast, DSLRs bury the vast majority of video settings in their menus, where you can never get to them in time for reactive shooting.

Unfortunately, while the NEX-FS100 has all the right controls in roughly the right places, they're disappointingly small and fiddly. The auto focus and expanded focus buttons are virtually impossible hit accurately while shooting handheld, to the point where shooting news or fly-on-the-wall stuff that requires quick responses will be extremely difficult, if not impossible.


Another big downside is build quality. Sony's earlier pro camcorders like the Z1 were tough beasts that could handle substantial bashing about in kit bags and aeroplanes and 4x4s in foreign lands. They had some vulnerable areas, like the boom attachment, but it was not uncommon to find a four-year-old Z1 in a newsroom locker that was covered in scratches, cracks, gaffer tape and blood-stains, and yet still worked perfectly. Having played with the NEX-FS100 for a fair amount of time, we just wouldn't have the same confidence in it. The modular design is partly to blame -- the grip attachment, for example, doesn't feel strong enough even when screwed in tightly. There is no handle on top of the camera except the mic holder, which screws into the inevitably weak hotshoe adapter. Also, the camera isn't dustproof or moisture-proof, so you'll just have to be careful with it.



Video Quality

Many years ago, we stuck a Sony Z1E onto a plank of wood beside an ancient Nikon F3 stills camera. Our purpose was to video an image of the world as seen by a true 35mm camera. That was the first time we saw digital video with shallow depth of field, as opposed to the hideous flatness of normal video, and it blew our minds. We got that same buzz all over again with the NEX-FS100, but mercifully without the splinters.


Our first job with the camera was to help out on a three-camera shoot of some amazing kids with learning disabilities performing Shakespeare. Despite the sunny day and absence of any ND filters, we were able to find shady spots were we could stop down to F6.3 to F11, and as you can see from our sample clip, this was sufficient to deliver a sense of depth in certain key scenes. There's a shot of a proud father taking pictures, where both the foreground and background is blurred just enough to make you concentrate on him and acknowledge him despite the fast edit. The same goes for the kids making up their messages in a bottle: the depth allows you notice and connect with each kid individually in a way that -- we believe -- flat video could never achieve with the same power.



Next up, we wanted to test the low-light performance of the camera and this where things started going wrong. It was entirely our fault, because we were on high after the daylight shoot and we were ready to believe that the NEX-FS100 could perform miracles. We duly turned up at a poorly-lit music studio in London's East End to get a few shots of a friend's band rehearsing. The studio wasn't dark, as such, but all the lights were in the wrong parts of the room, pointing in totally the wrong direction, and we had no time or permission to bring our own lights or move stuff around.


We grabbed a few shots at low gain and were extremely disappointed with the result -- it struck us as no different from a small-sensor camcorder. But we weren't really thinking straight, because the point of a large sensor is not that it improves light sensitivity at zero gain, but that it allows you to pump up gain without adding too much noise. Realizing this, we notched gain right up to 12db. On the UK broadcast scene, even this much gain is taboo and could render footage unfit for broadcast for anything other than news -- and even then, a news programme would only willingly accept 12db footage if the cameraman evidently had no choice, such as the scene of an accident shot at night. The force of habit made 12db feel "bad" to us, like a compromise too far -- and the image was still too dark and muddy to be acceptable.


When we allowed the camera to boost gain automatically, it instantly shot up to 18db and more. At this point, the image of the musicians became properly exposed, although it still looked unattractive due to the terrible lighting. There wasn't a great deal of noise visible on the small LCD, but all our instincts shouted at us that this 18db footage would be speckled worse than a speckled hen when we got home and saw it on a large monitor. So we switched back to 12db and did our best to hunt out decent shots at that level of gain, which turned out to be mission impossible. Eventually, we gave up altogether and went for a beer. Terrible mistake: we should have allowed the camera to shoot at whatever gain it wanted, and then done our best to re-work the lighting in the studio to make it more flattering. Had we done this, we would have discovered that our images were really as noise-free as they looked on the LCD. Where we expected to see speckly noise all over the shadows, there was nothing except, well... darkness.


Back at home, we realized our mistake and quickly organized a second round of low-light shooting at the Smithfield meat market. This time we allowed the camera to do what it wanted and we were stunned by the results. Despite the night-time hour and the generally weak and utilitarian lighting, the shots looked clean as a whistle and even engaging to watch.


We also grabbed a few shots on our trusty consumer Panasonic HCR-SD90, purely for the sake of comparison. The idea wasn't to compare a $6,000 camera with a $600 camera, because that would be daft. But we felt like we needed some reminder of what noise looks on a high gain image coming off a quarter-inch sensor. The picture of the market clock directly below is from the NEX-FS100 shooting at 18db, and the one below that is from the SD90 also shooting at 18db. Even with the images shrunk and re-compressed for this page, the purplish noise contamination on the lower image is just as obvious as the all-round cleanliness of the NEX-FS100 output. Sure, some noise is apparent on the NEX-FS100 shot of the two market traders further down the page, but the noise actually as a nice film-like quality to it, without much chromatic distortion. (Note, it's possible that auto gain notched itself up to 24db for this particular shot without us noticing -- it did rise into the mid-20s a few times during the market shoot without causing sufficient noise to alert us.)




The moral of the story? The NEX-FS100 shoots great footage at high gain of 18db and over, but that won't help you one jot if the lighting in your scene is genuinely crappy. If you get bad low-light footage with this camcorder, you can be pretty sure it will be your own fault.



Wrap-up

The NEX-FS100 is far from perfect as an all-around camcorder. It's particularly held back by the lack of auto zoom, minuscule buttons and fragile construction, all of which will limit the filming situations where this camera will be appropriate. Meanwhile, those who do make the leap of faith will quickly be forced to adjust their style in one way or another. To make the best use of a camera like this, you need to shoot quite traditionally: tripod mounted with a matte box, in a relatively gentle environment, with time taken to light and frame each shot properly before pressing the record button. (Read: too good to be true.) Shooting reactively for news or documentaries is not impossible, but it's difficult.

Some gadgets are worth making sacrifices for, however, and this is one of them. It delivers the raw cinematic beauty permitted by a large sensor, along with a smart lens platform and all the essential video and audio controls and I/O options required by any professional shooter. Muscling through on a DSLR or VG10 does not even compare.

It's not going too far to say that the NEX-FS100 is more than just a camcorder. To us, it represents a positive step along a path that we hope all manufacturers will eventually force each other into taking. For too long, digital video formats and cameras have focused on making things look more realistic: higher resolutions, higher bit-rates, sharper, clearer, smoother, more consistent images. At the same time, manufacturers have skimped on those key optical ingredients that give filmmakers the artistic freedom to make the world look better than it does in reality. That's why most handheld professional and consumer camcorders today have sensors no bigger than their ancestors from 15 or even 20 years ago, generally ranging from a sixth to a third of a measly inch. Admittedly, Sony could have been a lotmore generous with its Super 35mm EXMOR sensor, which is not nearly as big as it sounds. But we're not complaining, because S35 is plenty big enough to make stuff look beautiful.

No comments: