Video Workflow: Using RAW Files

So you want to work with raw video, huh? Good. You¡¯re ambitious¡ªI like that. Working with raw video, however, is not something to be taken lightly. It¡¯s a very powerful asset that has been made available to many consumers through a variety of affordable cameras from Blackmagic Design. But raw video takes up a lot of space and the benefits can be a little esoteric or unclear, especially if you don¡¯t come from a stills photography background. If you do come from a stills photography background, chances are you know about raw files and the benefits that they have, as well as some of the drawbacks. You may even have an established workflow with programs like Adobe Lightroom or Phase One Capture One that net you some great images. If you know the basics of raw files and what they are, feel free to skip the rest of this paragraph, unless you want a refresher.
Still with me? OK. Raw files¡­ Where to begin? What is a raw file? So glad you asked! A good way to look at a raw file is as pure information. If you snap a photo with your phone, unless you are using a specific app that does otherwise, you end up with a picture that you can see on your screen, send to your friends, upload to your social media, etc. Before that image made it to your phone¡¯s storage and screen, it has been processed, usually into a JPEG file. Without going into a lengthy and technical nerd fest, the data created, based on the light hitting your phone¡¯s image sensor, is processed and translated into the pixels that you can see and do whatever else it is that people do with digital images. Raw files haven¡¯t gone through the process and translation to turn them into images yet.

Simply put, a raw file is the data created, based on the light hitting the image sensor and stored without extraneous processing. It¡¯s not an image you can look at; it¡¯s a collection of digital code representing how much light hit each pixel on the sensor. It¡¯s called a raw file because it¡¯s raw data. Now you have an idea of what a raw file is as far as still images go, so onward to video!
The Nitty-Gritty
Raw video, basically, can be understood as a stream of single raw files captured at whatever frame rate is set in the camera. As a matter of fact, if you view a raw video file straight from your camera directly on your computer, you won¡¯t see a single clip, but rather a folder with the clip name containing individual raw files for each frame, making up your video when properly played back. Speaking of proper playback, how do you play back a video that¡¯s not a video, much less anything else like edit or manipulate it? Remember the JPEG file that could be viewed and shared on your phone? It went through a process that made it a visible image. Now if you have the raw sensor data, you can use a similar process to the kind used to create a JPEG, to make a playable video file. That¡¯s all well and good, but what¡¯s the practical difference between your camera processing the raw data first and processing the raw data on your own later?
Raw Video Wrangling
The procedure of shooting raw video is not so different from shooting regular video. You engage the Record Start/Stop function, during which your camera records the video, and then disengage the record Start/Stop to end the recording. You may notice that you have to change media more often when recording raw because the resulting files are huge in comparison to regular video files. Therefore, they can fill your camera¡¯s media really quickly and cause a cut in the middle of a shot if you¡¯re not careful. The benefit of those huge files can be experienced in the post-production workflow. This is where raw files shine.

The benefit of those huge files can be experienced in the post-production workflow. This is where raw files shine.

In most cases, viewing raw files requires the aid of a computer with some specialized software. Camera-specific raw-viewing software is usually free or included with the purchase of a camera that shoots raw footage. ARRI has its ARRIRAW Converter, RED has its REDCINE-X Suite, and Sony has various raw viewers for its different cameras. Professional editing or color-correction software like DaVinci Resolve or Baselight also have raw-viewing capabilities. The processing of the raw file to view a video image on a computer is commonly referred to as ¡°debayering.¡± Since most cinema cameras that record raw video use a bayer-pattern sensor, debayering is a necessary process that ensures colors are represented accurately. Cameras have dedicated debayering hardware, which can debayer an image in real time for easy full-resolution playback. Computers, without the aid of dedicated playback hardware like a Red Rocket PCI-Express card, which in itself costs as much as a high-end computer, will only be able to play raw files back at a fraction of their original quality. Some raw viewers and NLEs (Non-Linear Editing systems) that are compatible with raw files support GPU (Graphics Processing Unit) acceleration, allowing you to use your computer¡¯s dedicated graphics card to accelerate raw video playback. DaVinci Resolve, for example, can take advantage of a powerful GPU for better raw file playback with many different types of raw formats, including CinemaDNG, REDCODE, Sony Raw, and ARRIRAW.
The Workflow
While your machine may be able to play back raw files on their own, editing them and manipulating them is an entirely different matter. People who work with raw files have their own approaches, some of which are rather convoluted, so I decided to turn to a good friend of mine, Alex Hill,? as his approach can be applied to any existing video workflow, allowing you to utilize the advantages of working with raw files, even using modest computing hardware. Alex shoots commercials, short films, and music videos with his RED Scarlet Dragon, which uses the REDCODE raw format. After the shoot is finished and he has all the raw footage transferred to a hard drive, he goes through the clips in the REDCINE-X raw viewer, finds what he likes, sets in and out points, and converts only the footage he wants for editing into playable ProRes 4:2:2 files. This usually takes an overnight render session (as you may have already intuited, the raw workflow is not conducive to projects that require extremely fast turnarounds, so be prepared for long conversion times).

Once the video files are in a format that he can readily work with, Alex brings them into Adobe Premiere to make his edits, and applies color correction and a finishing grade all within Premiere. Now sometimes, that can be all he needs to do. However, occasionally he wants a little more from his video in ways that an NLE wouldn¡¯t be able to help him. If he finds a few clips that are in need of extensive tweaking, he goes back to the original raw clips in REDCINE-X and fine-tunes them to perfection before exporting them. The fine tuning that can be done to raw files is an order of magnitude greater than what can be done to standard video files. And this is the real appeal of shooting raw: all that extra space that the files take up, all the expensive media and computing horsepower that you require pays dividends here in post. Since raw files contain only sensor data, they open up a whole world of adjustments that could compromise the quality of standard video. For example, ISO sensitivity can be adjusted (to a point), white balance can be adjusted, and highlights that would normally be lost to clipping can be recovered (also to a point). Not only are more adjustments available, but they do not pose a negative generational impact as is sometimes seen with regular video when it has to be converted to another format and manipulated before being converted again for export later. Alex also told me that occasionally, the amount of flexibility provided by raw files allowed even him to compensate for inadequate lighting of his subjects. Now that¡¯s not to say you should shoot with the ¡°fix-it-in-post¡± mentality, but should you reach crunch time and have no other options, the flexibility of raw can swoop in and save the day.
Other Options and Conclusion
There are a number of other ways to process raw video, depending on how much you need done to your footage. Many people who commonly work with raw footage will make an offline edit with proxy clips (lower-resolution converted clips that require less processing power to play back in real time) and export a timeline to match up with their raw files. This allows them to make the edit in real time and then make all the aesthetic changes once they have their finished edit in place. REDCINE-X allows for the importing of XML files from common NLEs, DaVinci Resolve has evolved into a fully featured NLE on its own so you can edit offline and manipulate raw files without changing programs. Certain plugins or software, like Filmconvert, work really well with raw files to emulate the look and characteristics of film. Filmconvert works with standard video footage, as well, but it works better when there is more information available.

With raw files, the name of the game is flexibility, not only with how much you can do with the files, but with how many ways you can integrate raw footage into your workflow. For anyone who wants to start working with raw, the Blackmagic Design Pocket Cinema Camera is an affordable option that shoots 1080p CinemaDNG raw video, as well as ProRes to SD cards. As computers become faster and as new technologies become more affordable, raw video may become more commonplace. So learn now, start familiarizing yourself with raw files, and build a workflow that works best for you. My suggestions are only a starting point or a guideline to help you understand how raw video works and how it can be implemented. I¡¯ll leave you with another little bit of advice, no amount of post processing can compare to gaining actual shooting experience. Raw video should not be viewed as a crutch to save you from mediocrity; it should be viewed as a tool to complement your growing set of skills. As you grow as a filmmaker, you will learn to embrace the tools that you have, and raw video is a valuable asset that can really be worth your while.