9 minute read
Blackmagic Camera Test
We were first with the Blackmagic Pocket Cinema Camera but until now we haven't reviewed the original Blackmagic Cinema Camera. Here's Phil Rhodes' take on this fascinating device, which is now available for $1,000 less than the original price
The Blackmagic Cinema Camera is an interesting device, particularly in light of our recent coverage of luminance and monitoring. Its headline feature, in my view, is that it is probably one of the most cost-effective ways to get hold of a camera that will shoot in something other than standard video colorimetry – and has a very respectable 13-stop dynamic range
Blackmagic generously supplied a camera for evaluation along with a SmartScope Duo and one of their HDMI to SDI mini-converters so that RedShark and I could monitor HDMI devices as well and use the same device in post-production.
Handling
As an ergonomic proposition, the Cinema Camera is clearly very much a documentary device, designed to work the same way as a video-capable DSLR. While it's certainly possible to mount one on a set of rods and accessorise it for single-camera drama work, you'd probably prefer a separate viewfinder – something like a Cineroid – given the position of the monitor. Handheld it's fine if a bit chunky, and chunky really means solidly-built, so that's probably OK too. It certainly feels solid if not rather front-heavy with anything but a small lens mounted. We'll talk about the pictures at the end, but even looking at it on the back of the camera, it's clear that the claim of 13 stops of dynamic range in film mode, which is a lot, is not unreasonable.
The user interface to the Cinema Camera is refreshingly simple. The only key feature that's actually missing is some form of audio metering, which is odd considering Blackmagic went to the lengths of providing the thing with the balanced audio inputs which are so conspicuously missing on competing DSLRs. Blackmagic tell me it's one of their most requested features, so perhaps it'll appear in a future update. Meanwhile, it's possible to pipe it into something like a Smartscope Duo and select an audio metering mode, and meter the SDI embedded audio, if you're in a position to do that.
EF mount good for Canon Lenses
I had the version with the EF mount. This is good if you're using Canon lenses as the iris control is then available with the “next” and “previous” buttons which normally form part of the camera's transport controls. Personally, unless I already owned significant Canon glass, which tends to be less ideal for moving-picture work with its servo focus and lack of parfocality, I'd go for the micro-4/3 mount version which is adaptable to a wider variety of things. There isn't any electronic control available on the micro-4/3 version, which means that you can't get electronic iris control on EF mount lenses without a potentially-expensive active adapter. The choice depends on what you own and what you intend to use and the availability of the flexible micro-4/3 mount is a very good thing.
There is no auto focus, which would have been at least technically possible on the EF version with active lenses. While we wouldn't expect a non-reflex camera like this to have conventional autofocus hardware, which resides inside the viewfinder on a DSLR, it's possible to imagine autofocus being implemented based on real-time image analysis, as is done in some DSLRs during live view operation. This wouldn't have been feasible on the passive micro-4/3 mount, though, so it's no great surprise that the feature isn't there. Real cameramen laugh in the face of autofocus, of course, but it can be quite nice on run-and-gun documentaries. As an adjunct to this, the camera does provide a 1:1 pixel mapping when the display is double-tapped, which is really nice, and a peaking-style focus-assist feature.
Colorimetry
Colorimetry options are simple: “film” or “video”, which the manual indicates refer to log and Rec. 709 shooting, respectively. The key factor is that there's another film-or-video selection option in the monitoring options, which allows the user to view either the uncorrected log image as it's recorded, or to view it via a lookup table which creates something approaching a viewable Rec. 709 image. It's worth pointing out here that while the monitoring options affect the display on the back of the camera, the SDI output always reflects what's being recorded. This means there's no way to shoot log while distributing a viewable 709 monitoring image around set without extra equipment, which isn't entirely a plus. Right now, there also isn't a way to upload custom curves to the camera, so you have the option of seeing either unprocessed log (which is very flat and grey) or straight 709.
On-set monitoring
For dramatic productions, or anything that will be graded more than very slightly, people sometimes like on-set monitoring that will approximate the intended final look. To solve all your monitoring problems, you need another of Blackmagic's products, an HDlink, to go from the camera's SDI output (which is, remember, locked to log whenever you're shooting log), via a LUT perhaps defined in Resolve to an HDMI output. That the company can supply a complete system like this is quite nice.
Either way, monitoring 709 might seem a bit of a halfway house, because it's then more difficult to tell whether the extremes of exposure are being recorded properly or not. To an extent that's true, although the alternatives involve either carrying a waveform monitor, or really serious use of zebra stripes and other exposure aids, including good monitoring. You could, if you were a particular type of traditionalist, even use a light meter. It seems to me, though, that those things are not necessarily native to the sort of job for which the Cinema Camera is really designed, and thus it's a nice option to shoot log, see 709 on the back of the camera, and know that you're getting a bit more than you're seeing. Given the harshness of a 709 viewfinder, if it looks OK there, you can be reasonably sure that you aren't getting it so grossly wrong that it will look compromised.
Blackmagic SmartScope Duo Monitors
Because this article was written at more or less the same time as the second part of our test-and-measurement series on the use of waveform monitors, while shooting, the company also supplied us with one of their SmartScope Duo monitors.
The SmartScope is a three rack unit high device with two independent 8” TFT displays, each of which can be assigned to behave as either a picture monitor, a waveform display of either combined or RGB parade variety, audio analysis (with a phase plot of two user-selectable channels), or a vectorscope. One of the incidental benefits of the digitisation of production technology is that producing correctly calibrated instrumentation is no longer a matter of fine adjustment and components expensively crafted by master craftsmen; rather, it's simply a matter of mathematics, which is what allows this reasonably inexpensive product to exist.
Major Test Gear
For around £850, getting two bits of major test gear is a solid deal. In the unit I received there was a slight colour offset visible between the two displays when they both displayed the same video, but it's not noticeable on non-photographic material such as a waveform display. This it isn't intended to be a reference monitor and for the money it's a steal. What's really nice is that the two monitoring units have inputs and (reclocked, happily) outputs, so it's trivial to daisy-chain them together and view two different sets of test data about the same signal, or in a situation where you aren't using the device as an adjunct to calibrated monitor don't ring, to view the signal that's actually under test.
The only slight irritation I have with the SmartScope Duo is that it is entirely controlled by either USB or Ethernet. The network option is probably great for a situation such as an outside broadcast truck or studio where there might be many of these, perhaps one per camera, which need to be controlled remotely. In a grading suite it's nicer to have a physical control to grab, rather than have to tab out of a grading app to tweak settings using the software, but again, that's not unreasonable at the price.
As the current SmartScope is a rack-mount unit, while it wouldn't be unreasonable to put it in a little rack case and tote it around, it clearly isn't intended to be mounted on a camera rig or used in hand. There's no word yet on the future possibility of a smaller, more hand-portable SmartScope Mono, but I can't be the only person to whom this possibility has occurred.
So what about those Blackmagic Pictures?
Let's deal with the main issue first: one thing this camera does have in common with its DSLR competitors is a rolling shutter, which is almost inevitable on current cameras and the acceptability of which is therefore a matter of degree. Some DSLRs have really atrocious rolling shutters, whilst an Alexa has a rolling shutter that's barely perceptible (and some Alexas have mechanical shutters too). The forthcoming big 4K brother of the camera I have here enjoys the considerable advantage of a global electronic shutter, although that and the increased resolution does cost it somewhat in dynamic range (only a stop, by Blackmagic's measurements, presumably because the sensor is larger). The conclusion, based simply on waving the camera around and observing the results, is that the rolling shutter on the 2.5K Blackmagic Cinema Camera is rather more visible than I would really like, about the same as some DSLRs, so this is never going to be a horse for any course involving lots of hyper-violent handheld running around and shaky-cam, which is a pity in a camera clearly aimed at hand-holding. It is, however, as usable as any other rolling-shutter camera for the majority of work that doesn't need to look like the opening scene of Saving Private Ryan.
Other than that, complaints? Very few.
A very minor issue shared with many CMOS cameras is that the sensor will begin to reverse out to a noisy patch of black and purple in areas of very (very) extreme overexposure. The first Red did this and so did the original cinema camera, and firmware fixes have made it a lot better than it was. I had to work really hard, using a focussed-beam LED flashlight capable of very, very high intensity, to reveal the problem, and at that point it'll be buried in the middle of a huge white flare in any case, and trivial to fix. Not a big deal.
It would also have been nice to see higher frame rates – I hadn't realised my own prejudices in this regard until I realised that something that doesn't even do 60p now feels slightly old-fashioned. The upcoming 4K camera offers no comfort in this regard either. In some ways it's good that Blackmagic haven't chosen to push this sensor to do higher frame rates when that would almost inevitably introduce greater noise, but if there's anything coming after the 4K version, presumably this will be a target for improvement.
Formatting
And finally, a word about disk formatting. The camera supports SSDs using either the exFAT filesystem or the Apple HFS+ standard. After I'd read the supplied HFS+ SSD on a Windows PC with the MacDrive software, which Blackmagic recommend, the camera refused to recognise it. There is no loss of data involved in this, as the drive remains readable on the workstation, but the camera cannot format disks itself and performing the required reformatting under windows requires either MacDrive or some moderately hairy hacking with the disk-part command-line tool. The flaw could be in either MacDrive or the camera's firmware, but it might be worth avoiding HFS+ disks until we know more. ExFAT is more widely compatible in any case.
I think that the pictures, after all this, are rather special. That wide dynamic range makes mixed sunlight and shade subjects desirable, for once, as opposed to a liability. It's always difficult to describe the niceness of pictures without it becoming a stream of opinions (the word “painterly” deserves the swear-box in discussions of cinematography), but it seems to tolerate hard sunlight in a way that video cameras often don't. Perhaps it's just a side-effect of the nice dynamic range, or the handy “iris” button which ensures nothing is clipping, but the pictures immediately put me in mind of the Michael Palin travel documentaries. I think it'd do well on a round-the-world trip.
Adobe DNG
Outside documentaries, top-end film-makers are using these things as crash-cams (lower-cost cameras intended to reduce the insurable risk on big stunts and visual effects) for Alexa shoots and I can see why. It's not very fast by modern standards; the highest selectable ISO is 1600, but noise is reasonably well-controlled and overexposed highlights enter the clip without unpleasant side-effects. There's nothing quite like true uncompressed recording, either, and it's to a sensible format: Adobe's DNG. This requires a lot of bandwidth and I do wonder somewhat about the robustness of the SATA connectors that Blackmagic rely on to mount the required fast disks in this camera. I wondered much the same about the Hyperdeck recorders, though, and we haven't heard a storm of complaints.
As a matter of opinion, I don't think that the Rec. 709 LUTs that Resolve has for this camera do it justice, although that of course is the problem with 709. I'd like to know whether Blackmagic have obediently created a strictly technically correct 709 LUT, per the standard, which tends to lead to this sort of problem. Many manufacturers instead create LUTs that make things look reasonably pretty on 709 displays but may not be to the letter of the standard. Of course on a camera of this type you have a choice and that's great, so if you see some Cinema Camera footage and it looks rather over-saturated and clippy, don't assume that's what it all looks like. It's much better than the default LUTs make it look.
Compliments
So, ultimately, if you can avoid the rolling shutter issue that's common to many cameras on the market today, it's capable of some very nice pictures not only for the money but also in general, and I know of no higher compliment for a camera. As a value proposition it sits in a place neatly between a few other options – although at this point, price reduction or not, I might well hold off on a purchase until I'd played with both the 4K version, which is better, or the pocket version, which is smaller.
But I'd be ready to conclude that the current cinema camera was still a great deal.
First impressions of the Blackmagic Pocket Cinema Camera here
Tags: Technology
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