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Capturing HDMI Video


A quick guide to getting the best video from a D4 or D800

The D4 and D800 models produce "clean video" on their HDMI ports, which has excited the video world, as theoretically this means that you can record uncompressed (or lightly) compressed video and get broadcast quality video out of the Nikon DSLRs.

As I've discovered, the dream is possible, but to get to its promised land is not a journey without perils.

First up, we have the cameras themselves. Nikon has done a woefully poor job of documenting how to get the best possible video from them, or even the steps you have to go through to get clean video out the HDMI port in the first place. That's something I'll fix in my Complete Guides, but the quick and dirty is this:

  1. You need to take the internal storage cards out of the camera (XQD and CompactFlash on the D4, CompactFlash and SD on the D800). This isn't technically necessary, but there are things you can do if a card is in the camera that'll reset the HDMI output to 720P that don't happen if no card is in the camera.
  2. You set your frame size/rate via Movie Settings, as usual.
  3. You need to turn HDMI/Advanced/Live view on-screen display to Off and HDMI/Advance/Output display size to 100%. These are not the defaults!
  4. Depending upon what you're trying to do and what quality you desire, there may be more HDMI/movie settings you'll want to make. One to pay attention to is whether you want to output full or limited range. If you're new to video, you're going to get caught by this one eventually. Best choice: Limited range, as it puts black and white points within broadcast video safe limits.
  5. If you're doing long takes, you must set CSM #C4 Live View to No Limit.
  6. You generate the HDMI stream by using Video Live View (i.e. move the Live View lever to video, press the Live View button)

Okay, so let's assume that we've got the camera set right, what do we record to? Right now there are a half dozen or more basic options readily available on the market and available from places like B&H. The ones I've tried, from cheapest to most expensive, are:

  • Blackmagic Shuttle. (Warning, the Shuttle only records uncompressed video, the Shuttle 2 also records Avid DNxHD compressed video, for which you'll almost certainly need an Avid codec to do anything with, and which may require you to transcode [recompress into another format] to edit, depending upon what you use.) The Blackmagic Shuttle uses expensive SSD (solid state hard drives), and only certain ones at that. Basically, the Shuttle is a dock for a drive with some connectors and recording/playback controls on it. Its function is simply to record or playback video (though it has HDMI passthrough if you'd like to hook it to an external monitor). The Shuttle has a basic battery in it, too, so it's portable. But that battery is built-in and thus you have to feed AC power to the unit to recharge, making that portability a bit compromised.
  • Atomos Ninja. This is a more complete solution in that it has a touch-screen LCD and dual removable battery capability, meaning it's a real portable solution (while using it you can be charging more batteries on the supplied dual battery charger and hot swap a battery for a new one when it goes low). The LCD provides direct control over all functions and some information during recording, and it also supplies a playback option. The Ninja will take regular laptop hard drives, though you need to be careful not to bump the unit if you're recording to rotating media. It records in various forms of Apple ProRes, which is a common codec and supported by virtually all Macintosh editing solutions (Windows users can download decoders that understand this format for free).
  • Aja Ki Pro Mini. Yet a different approach. The Aja has two CompactFlash cards on it, and records in a variety of Apple ProRes formats to them. But these cards need to be very specific ones, generally 90MBs or faster, of which the Sandisk Extreme Pro make up half the supported card list. The Aja is designed for more sophisticated video productions, and has XLR audio connections, which means it can serve as a basic mixer, amongst other things this implies. The unit is not battery powered. The interface is more complicated than the Blackmagic, but more informative, too.

I'm not going to get too deep into features and capabilities here, as this isn't a Video Pro site. The main thing to note is that all of the above units are capable of recording the Nikon D800 and D4 clean HDMI if you get everything right.

Yeah, there's that again. I already dealt with a bit of the camera confusion, but there's plenty at the recording end, too. With all three units I found that I had to update firmware (even bought new after the cameras came out), as the companies are all scrambling to keep their units up to date as new cameras get launched with new little gotchas. Moreover, all these companies could use some more work on their manuals. Blackmagic's latest manual is straight-forward enough, but it assumes you know what you're doing ;~).

I found minor issues with the hardware in almost every case, too, despite each of them being built like a brick (like most pro video equipment is). My Blackmagic Shuttle has a tendency to drop the audio signal on the HDMI port. My Ninja likes to hold onto drives and not release them from the slot despite pressing the release button, and the touch-screen isn't always responsive. It also dropped the signal once after an hour of recording. My Aja's fans means it needs to stay isolated from microphones. Nothing major, but these are not consumer devices and aren't vetted like those. There may still be some additional quirks I'll discover in extended use, indeed, I fully expect to find some.

One further comment: HDMI signals were originally designed for consumer electronics components, and we're making them do things that they weren't exactly designed for (HDMI cables don't have professional-type latches on the connectors, making the possibility of intermittent signal more prevalent when jostling equipment). In tens of hours of recording with these devices, both in test and in real video situations, I've seen multiple instances of the camera and recorder losing handshake. That can be extremely frustrating when you're recording something that won't get repeated (i.e. live versus staged).

So let's hook them up and see what happens, shall we?

  • With a Blackmagic Shuttle (original), there's not much you can do. Put an SSD into the Shuttle, plug in the camera, put the camera in Video Live View, wait for the Video light to show on the Shuttle, then press the Record button. You'll be chewing through 12GB a minute and recording 10-bit 4-2-2 video plus audio (sometimes ;~). You'll need an eSata cable for your SSD on your computer to get your video over to your computer. Files are saved as Quicktime .MOV with no compression.
  • With a Blackmagic Shuttle 2, you can select compression (AVID DNxHD), but only with the Shuttle 2 connected to your computer's USB port, so do that before you head out. You can have that put into an AVID or Quicktime container (and you'll need to download and install AVIDs codec for your computer to be able to play those). You won't chew through nearly as much drive, but you are recording compressed now, though a very high quality file results.
  • With a Ninja you can do a lot of things on the unit itself, such as format drives and set compression settings. Three forms of ProRes are supported, including HQ, which results in compression that's essentially visually lossless. You get Quicktime .MOV files. Atomos supplies a drive caddy for your computer with the unit, so all you have to do is take your drive out of your Ninja (if it will let you ;~), and put that into the cradle attached to your computer. Now use your usual video workflow on that. The Ninja is nice in that you can review captured video in the field, plus it will accept regular laptop hard drives (Atomos supplies two empty drive caddies). One thing I didn't expect is that there seems to be a time limit or file size on individual clips on the Ninja.
  • The Aja has a bunch of buttons and a small LCD on the front, and like the Ninja this allows you to do things like format cards, select compression, and other less common tasks.But you really need to study the manual and practice using those buttons, as the UI is a bit strange and the LCD slightly cryptic. If you've got an HDMI monitor hooked to it, you can perform review, as well. So, we put cards in the top slots, select our ProRes compression level (which will have you consulting the manual to figure out the sequence of buttons to press, at least initially), then fire up the camera and press the record button on the Aja. If you're recording analog XLR audio, you can do that directly into the Aja (and monitor via LED level indicators and headphone). When you're back at your computer, you just treat your CompactFlash cards like any other video media you bring into your workflow.

So does any of this make any sense to do? And which one should you consider?

The big clamor was about uncompressed video. The Blackmagic Shuttle will do that for you, but are you really sure that's what you want? You'll chew through expensive SSD drives very, very rapidly, and that's going to mean huge files and backups (you are backing up your work, right?). For uncompressed, we're in serious Video Pro territory. You've got a massive RAID system that delivers high performance access to your files and think nothing of terabytes of data. If that doesn't describe you, don't go uncompressed.

Apple ProRes HQ is actually a very good compression format that results in very high quality files of moderate size. Basically figure an hour for 100GB. ProRes422 will get you almost two hours for 128GB and is still a pretty good format for recording high quality output (better than what the D4 and D800 output directly). Indeed, I think ProRes HQ lines up very well with the clean HDMI out of the D4 and D800. Thus, the Ninja and Ki Pro Mini are both interesting choices.

The Ninja has several key advantages:

  • Direct review in the field without adding another monitor
  • Dual battery backup
  • Ability to use rotating hard drives (less expensive for long takes)
  • All controls very clear once you figure out the interface

The Ki-Pro Mini has several key advantages:

  • Uses CompactFlash cards (though expensive ones)
  • Can act as an XLR audio input recorder/mixer in tandem with the video
  • Has SDI capability, as well, should you have pro video cameras that use that

For me, the battery and self-contained aspects of the Ninja makes it my preferred choice, though I'll continue to evaluate all these units. I'm finding that I don't truly need uncompressed video. I also prefer the battery-powered portable solution (though you may need more expensive SSD drives in the Ninja if you're jostling it during recording).

One word of warning: you're in complex territory here. If you really need better video than what the D4 and D800 can do internally, then you need a lot of external components (video recorder, audio mixer, etc.). You're nearly in DIY (do it yourself) territory, as the current pro video world is a lot of small niche companies doing small niche products. You'll be spending a lot of time reading manuals, updating firmwares, connecting and securing cabling, and far more. If you thought still photography was an expensive hobby, video is more expensive and more nerve-wracking (more can go wrong).

Comment: I noticed one discussion about this article elsewhere where people felt that my comments are too harsh because I'm "out of my element." I'll remind you that I have a BA and MA in television production and filmmaking. I first started using digital video equipment in the 1970's, and have been involved in a number of video projects ever since. My comments here are about small-scale video production. If you're a Hollywood union crew shooting video, you've got a fair-sized crew to deal with all the little details and you've likely got a lot of backup in your support truck. What DSLRs (and other still cameras with video) enable are much more portable, small-scale productions, where one, two, maybe three people are dealing with all aspects from capture to edit. My comments are centered on that kind of use, and the D4 and D800--especially if you're trying to capture high-quality footage via the HDMI port--certainly make this complicated, with a lot of small details and interactions that can make it so that you don't get what you want. My point is that Nikon has a lot of things to address in the UI to make video a simpler, more reliable thing to do with these cameras. The key video attribute that distinguishes a D4 or D800 from the competition is the clean HDMI signal. But you only get that if you're paying attention to all the settings all the time. In particular, there's no way to set the camera once for HDMI video out and restore that if you make other settings during your still shooting. None. This is a mistake, and the first time you record footage in a format other than you desired, you'll understand that. My current method to avoid this is simple: I put the HDMI-based settings in every bank. That way, when I do use the banks for moving between still settings, I don't screw up my HDMI output. This is a common theme in the current state of cameras: make the user do something extra to get around what is really a design problem in the first place.


 

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