- Ascertain the target output format at the outset (if you control your own format destiny, skip to 2)
- Decide who, if anyone, controls the color intent at the outset (if no one has specified how the footage must look on set, skip to 3)
- Leave R3D and 4K behind as soon as possible (and no sooner)
- Take control of sharpness, noise & more during conversion; don’t leave these to tools that can’t work with them
- Make use of great free and cheap tools if you can’t just rely on Scratch
The RED ONE camera is innovative technology that will only improve. Someday, perhaps the good people at RED will anticipate the workflows most often used to work with their footage and offer specifications that help ensure their users’ success; for now, however, the following incontrovertale facts about RED often guarantee the need to make decisions more or less on your own:
- no tools exist to write an R3D file (although several can read them), nor does RED endorse any alternate standard for converting their footage
- the color intent of an R3D file cannot be controlled (although it can be specified)
It is no coincidence that the happiest RED post-production pipelines have been the ones in which a given studio is master of its own destiny when it comes to the color look and output format of its footage. Likewise, hapless studios have in some cases encountered actual crisis when confronted by the demands of the director or DP to match the footage to how it looked when shot, or when required to deliver a particular format to another facility (typically for the purposes of conforming and finishing, often on a system standardized around 10-bit log Cineon DPX files).
Things can only get better. Meanwhile, here are some tips to keep from going crazy.
Tip 1: Decide target output before beginning post-production
Nothing screws up a RED workflow like the surprise discovery that output is required in an unanticipated format. Conversion takes time, and certain types of conversion, such as between different types of log files, are not at all straightforward, if supported at all in your toolset. And if the decision was made at some point to convert to a lossy format like ProRes 4:2:2, valuable that someone else needs may have been thrown away.
It’s essential to know whether you are finishing your project in-house, according to your own specifications, or whether at any point you will need to hand off files to another facility.
Why? An R3D file will inevitably give birth to some other file format before it is seen outside your facility, because there is no means to write an R3D file. Depending on who is finishing it, this conversion may involve the application of LUTs and log color. If you’ve never worked with a LUT or converted a file from a log color space, that’s certainly nothing to be ashamed of, nor is it a prerequisite for working with RED files. On the other hand, if your work is headed to a DaVinci or Lustre for finishing, you may have no choice but to dig in (although DaVinci has recently announced support for R3D files, so if you’re not doing anything but cutting them together, with no need to re-render, you might be okay).
No matter what – and this is important – you won’t be outputting 4K (4096 pixel wide) R3D files, for a couple of reasons:
- (once again, with feeling) you cannot write an R3D file
- in 99.9% of cases there is no means to project 4K
Therefore, if the project is to be finished in-house, skip to tip 2 (if necessary) or more importantly 3, where I will try to influence you nonetheless to convert to some other format. If your project is to be finished at another facility, find out where and how the conform will be done, because it may dictate the type of file you give them. Only Assimilate Scratch and Quantel systems such as Pablo (and now, da Vinci Resolve) can accept R3D files natively; for Lustre you are likely to have to provide DPX files in 10-bit log format, and converting to this format if you’ve been working in another can be tricky and cause extra days of conversion time that you haven’t planned for, depending on the size of the project.
If, because the delivery format will be DPX files, you elect to convert to DPX at the start of the process, check out tip 2.
Tip 2: Decide who, if anyone, controls the color intent of your source footage at the beginning
Many RED shoots treat the footage as if it were film; what is seen on the monitors at the shoot is the equivalent of a video tap that gives you a rough guide but not the look of the final image, like you might have with a standard 10 bit 3 CCD video camera. This is because the R3D file explicitly does not offer control of color intent; quite the contrary, essential information such as the ASA/ISO and source and target color space are essentially arbitrary (and out of your control if you pull the R3D directly into, say, an Adobe pipeline).This has a disadvantage, as RED does not have film’s dynamic range, so a light meter won’t necessarily pick up highlights that could clip.
Many DP’s know how to avoid clipping digital video, but will not be so ready to let go of shooting footage with the expectation of how it will look in post-production. It is certainly possible to preview RED camera output as REC 709 video and then make that the intended color space (in a tool such as REDAlert);
you can even create a color look in REDAlert or Scratch and transfer it to an SD card to load it directly onto the camera as a preview LUT.
Many people don’t know this, and so it is the rare shoot on which this happens. Having now tested the use of SD-cards for this purpose hands-on, with a Build 16 RED camera proved that, as of now, you can preview Rec709, but no other output profiles, and color profiles cannot be transferred from REDAlert to the camera – or even from the camera to REDAlert – but only from one RED camera to another. RED has strongly hinted this will appear in a future build. Thanks to reader Steve Harnell for the tip.
If, in the more typical scenario, a shooter was going for a particular look on a REC 709 (HD) monitor, you can at least assign that profile is assigned to the footage. Here’s where it gets tricky – this is one subject that goes beyond the scope of this article: in REDAlert, you can specify a Color Space that corresponds to that of the shoot, load or save a preset with specific settings, and those settings can ride alongside the R3D file as an RSX file; they are applied, for example, to the QuickTime files that point to that R3D file, so if you open the _P, _H or _M files that are also riding along, boom, you get a QuickTime with color adjustments as soon as you rewrite them (which you can also do with REDAlert) so that they are ready to use with color intent inside applications that work with those QuickTimes, such as Final Cut Pro. There are enough snags with this process that it is more appropriately saved for a more specific follow-up in a later article. Watch this space.
However, many other places that R3D file could go, including straight into After Effects or Premiere, do not recognize that RSX file and offer effectively only the raw R3D data plus a few rudimentary controls over grain and so on (covered in tips 3 and 4).
If I’ve lost you with this talk about REDAlert, hang on; I’ll try to clarify somewhere around tip 5.
Tip 3: Leave R3D and 4k behind as soon as possible (and no sooner)
This tip is the very heart of my argument here, and no doubt it is the one that will cause the most internal strife for conscientious video nerds.
Repeat after me:
I cannot output 4K R3D files. The longer I drag around huge entire R3D files when my actual plan is to scale them down (particularly to SD), the more misery I cause myself.
True story: a colleague for whom I have the utmost respect (name omitted to protect the innocent) posted a standard def, D1, 720 x 486 commercial full of medium close-ups perfectly shot on greenscreen with source 4K R3D files natively in After Effects. Despite that the images contained over 25 times more image data than his output required, he and his team evidently fell in love with how great the keys looked. When his renders failed he forced memory settings in After Effects to use only the disk cache for memory (because he was outstripping the 3 GB per processor RAM limit for this 32-bit app) and the renders then, instead of just failing, merely required several hours.
For 15 seconds of SD broadcast video. It didn’t take me that long to render a good greenscreen on a beige Mac in 1996.
R3D files therefore play on that oldest of human imbalances: fear vs. greed.
Fear comes from having been told that the R3D file is the equivalent of a film negative. You’ve heard what they used to do with those negatives, and what would happen if there was a scratch in any of them. You give yourself the goal of preserving the content of that negative at all costs.
But you are only partially right; you must preserve the negative, but at the least possible cost.
Greed happens when you attempt your first greenscreen key of a well shot R3D file. Yes, it can be a breathtaking experience, pulling the most effortless and beautiful key you’ve ever seen. Its siren song calls out to you, telling you to preserve those beautiful semi-translucent wisps of hair as if your life depended on it.
And then you see the result in D1, and you want to scale it 500% (possible!) so everyone can see what’s really there.
My role here is to talk you down off the ledge when your 15th render has failed because of memory errors. Here is what you must do: you must losslessly and effortlessly convert that R3D file down to whatever format you can actually use.
What did I just say? That’s right, you must throw away data that you can not and will not use. But – and this will make you feel better – you must also not throw away any data that you actually can use.
Right now it’s almost as if you must hire a consultant to tell the difference, which means that full exploration of this topic will have to happen in a future article which I may or may not entitle, “Convert an R3D with Confidence.”
For now, I’ll give you an outline. Yes, I know full well you’re not going to trust your half-million dollar commercial to an outline, but see if there’s anything here you can use: your source R3D file can be converted to several formats that are still better than your delivery format, and effectively lossless.
Your best bet in my opinion is to choose either 16 bit linear TIFF or 10 bit log DPX conversion and write image sequences; either format has more headroom than RED’s 12 bit linear sensor. You also have the option of QuickTime in whatever format suits your post-production pipeline – say, 4:4:4 10 bit Blackmagic HD, which will still key like a dream if well shot and won’t give up much in the way of color fidelity despite being a linear format.
“Uh,” you say, “but my situation isn’t that simple. The DP was like a drunken sailor, mixing in 50 fps 3K and 120 fps 2K footage of shattering glass and water droplets, framing wide on the 4K so that we would only use a portion of the shot.” In that case you must take extra care to maintain each of those formats without keeping data you don’t need, but the bottom line is simple: sooner or later, you won’t be in full 4K (or probably even 3K) and sooner is better than later when it comes to dragging files around. This doesn’t even include the fact that you may only need a two second clip out of a two-minute long take, and if you stick with R3D, you must drag all 2 minutes of footage with you everywhere you go.
Give tip 2 its due, but keeping in mind your target, convert to 2K, 1K or whatever matches or slightly exceeds output, and forget that the R3D was ever meant to be seen by anyone. It’s your secret weapon, and your renders will seriously be 10-20x faster.
The caveat is that if you’re simply cutting and outputting, no effects or color correction, you could conceivably stay in R3D all the way until it’s time to render output or hand it off. That still leaves a couple of potential concerns.
Tip 4: Take control of sharpness, noise and more at the time of conversion
Once again, this may be fodder for another article another time, but RED output will look a little soft at 4K not because the camera doesn’t truly deliver 4K – it does (although careful tests show it resolves somewhere closer to 3K) – but because the camera performs no sharpening. Those of you who have worked with video cameras for the last couple of decades may find this to be a shock, but rather than being something you must try to eliminate, sharpness is something you must in fact add to R3D output.
Use the Debayer Detail setting in REDAlert (as well as the RED settings in After Effects and Premiere) – set it to High and you have at least introduced a modest amount of sharpness, but be prepared to add more as needed. The problem is rarely too much.
Similarly, although RED footage is already way lower on noise than pretty much any film footage and most video footage you might have used, you have control over the amount of Chroma Denoise and OLPF Compensation. OLPF stands for Optical Low Pass Filter; its target purpose is the elimination of moire fringing, but you may find it pleasingly de-noises your image overall. The amount of Chroma Denoise required may be none, or you may find that one of the 6 levels of denoise to the red and blue channels helps your shot.
The simple act of down-sampling resolution can and will make your RED source look sharper at 720p or D1.
Tip 5: Make use of great free and cheap tools to help your workflow
If you’re on a Mac, there are several tools available for free or cheap to help you complete the RED workflow. I’ll focus on a couple of them here, and save a more complete rundown for another time.
REDAlert is the most useful RED-related tool you can download for free. It is essential that you get at least this software for two reasons: first, it is the best place to do basic adjustments to an R3D file, and second, it includes Redline, the command line utility used by many other free and shareware apps to work with those files. In a future article I share more about how to use REDAlert to understand the R3D file, but it’s one place you can create your main color settings, making certain that your highlights are balanced and not clipped using the Histogram along with the Exposure and DRX controls, and where you can assign the target color profile for output. You can even output a test file or sequence here, although it’s not recommended for converting multiple sequences; there are better tools for that.
If, for example, you have been taking advantage of Final Cut Pro’s ability to edit the QuickTime movies that link to R3D files, there are several ways to get your EDL to where you can convert those files, with handles, to a format you can use. One of these is Monkey Extract, whose free version lets you do the basic conversion to DPX, TIFF, or even QuickTime, without all the geeky unfriendliness of Crimson Workflow (also free). Granted, an XML-based EDL limits you somewhat: multi- and sub-clips may typically be off-limits or require a work-around.
However, this approach allows you to convert the R3D to a file that has no less color data than your source, and no greater resolution than you need for your output. Again, if you weren’t reading carefully, the RED camera records 12-bit images, so a 16 bit linear TIFF or 10-bit log DPX has more than enough headroom to handle the image data at a fraction of the R3D size. Even a carefully written 10-bit linear 4:4:4 image can effectively have no less data than the source; at some point (again, later, tests in hand) I will attempt to explain more about how to unlock the true dynamic range of an R3D.
Meanwhile, if you need to convert to 10-bit log DPX files, Glue Tools allows you to continue to work with them in Final Cut Pro. If you’re on Avid, you can find more information about the RED workflow here (at this writing I personally have no hands-on experience with RED in an Avid workflow).
These 5 tips are merely a starting point for more discussion. Overall, keep in mind that although conversion of R3D files requires expertise to be done right, and can require extra days of post-production depending on the size of your project, not to convert if you have that option (working with native R3D files in an application that can handle them such as Adobe After Effects) can cost you much more in terms of slower and less stable workflow as even the most powerful system struggles to work with an image sequence made up of huger-than-necessary frames.
If there’s one key take-away from this article, it’s this: for the vast majority of projects, preserving full 4K (or even 3K) data is not your main goal; you will find the greatest success by converting to a format that keeps only what you need.
(Comments, questions and complaints most welcome – they will help shape follow-up articles)