RED Post – the Easy Way II

The RED camera company has succeeded in shaking up the industry and getting all other camera manufacturers to rethink what a digital cinema camera should be. This year, the ARRI Alexa presents the first serious challenge by another system designed around a camera raw workflow. Although RED maintains a resolution advantage, which will increase with the forthcoming Epic, there are many other reasons producers might opt for an Alexa, a Panavision Genesis, a Panasonic VariCam/3700/2700/3000 or a Sony F23/F35/F900/F800.

One of the strategic errors that I feel RED made was to emphasize resolution over workflow. By doing so, their innovative approach was tagged early on by detractors as difficult and time-consuming. It’s actually rather straightforward with a lot of versatility and can be adapted to many different production needs. Unfortunately, no matter how easy it has become today, RED will continue to battle this perception issue. This is exacerbated by RED itself, who has never provided good documentation for its products, especially the post production tools. A byproduct of the “perpetual beta” mode in which the company operates.

Native vs. non-native

I haven’t been a big fan of dealing with the camera raw files during editing, opting instead to pre-grade/render/export the camera files first into an edit-friendly format. If you search through the RedUser forum, you’ll find plenty of posts pointing out that the preferred feature film workflow is to export flat-looking DPX files for conforming and grading in DI systems like daVinci, Pablo and Lustre. This is a common workflow for DI and digital acquisition. I’ve demonstrated some of the latitude such a flat image can offer, even though it isn’t camera raw any longer.

Apple and Assimilate were early adopters of being able to access RED’s raw color data. Since then, RED developed an SDK that has allowed many other NLE manufacturers access to the raw data through this spec. Now others, like Avid and Adobe, can open and manipulate RED files based on the camera raw data. This gives editors wide latitude over how the image can look, without being stuck to a “baked in” camera image as a starting point. It’s like editing from transferred film, yet having access to the original negative in the NLE. I’ve recently reviewed Avid Media Composer 5 and Adobe Premiere Pro CS5 and spent some time testing this out. Both do a very good job with native RED files, but my conclusion is still that an offline/online editing methodology works best for complex, long-form productions.

FCP’s Log and Transfer

Last year, I edited 90% of my projects with Final Cut Pro, so I’ve decided to revisit Apple’s “native” RED workflow with a fresh eye. FCP does not let you work directly with the actual .R3D camera files. Instead, RED files are imported via FCP’s Log and Transfer module. Here you have two options: a) import as native REDCODE (the .R3D file is copied and rewrapped with a QuickTime container); or b) import/transcode to an edit-friendly codec, like one of the ProRes codecs. During Log and Transfer, you may select one of several colorimetry presets or “as shot”. Once imported into FCP, you can’t access the source settings (as in Media Composer or Premiere Pro). Instead, the workflow is designed around Apple Color, where the tools are provided to once again access the camera raw color data.

A lot of the RED appeal is over the fact that the camera records 4K images. 4K refers to a frame size of 4096 x 2048 pixels (2:1 aspect ratio). The RED One camera is capable of various frame sizes, but 4K appeals to indie filmmakers as some sort of Holy Grail. That’s in spite of the fact that most feature film DI is done at 2K sizes and some films are even posted using HD video (1920×1080) as an intermediate step. Avid Media Composer 5 limits you to an HD frame while Adobe Premiere Pro CS5 and After Effects CS5 will let you work at 4K. FCP doesn’t allows 4K, so the effective workaround is to downsample the 4K RED images to 2K (2048×1024). FCP and Color deal with this image size quite effectively and i/o hardware like the AJA KONA3 includes presets for 2K images. I like the idea of 4K at the camera, but I’m perfectly okay with 2K and HD in post.

Size and debayering

The downsample issue is confusing, because it affects image size and debayering – the process that turns raw data into RGB video. Unfortunately, RED hasn’t provided clear information as to what is really happening. The rule of thumb is that 2K images are downsampled as 1:1, while larger images use a 2:1 ratio. Since you have no control over the debayering settings in either Final Cut or Color, the belief expressed by some users is that RED’s own post tools, like REDCINE-X, yield better image quality. I haven’t seen anything that’s an issue in my own testing and some of the threads at RedUser would indicate that the results are comparable in head-to-head testing. You’ll have to judge for yourself.

If you are planning to post via this workflow, then it’s important to think about the right image size before production starts. If you shoot at 4K 2:1 (4096×2048), the resulting 2K 2:1 image (2048×1024) in FCP will either have to be center-cut (a blow-up with some cropping on the edges) to fit an HD (1920×1080) frame  - or it will have to be displayed with a letterbox mask.

Color scales the 2K image in the Geometry room as it renders. Since the majority of producers using this workflow are mainly interested in a proper HD image (1920×1080), I would recommend that the original footage be recorded in either 4K 16:9 (4096×2304) or 4K HD 16:9 (3840×2160), aka “quad HD”. The former gives you a little wiggle room for minor reframing, while the latter is an even multiple and will provide the most accurate downsampled image.

RED step-by-step with Final Cut Studio

Let’s take a look at the recommended Apple Final Cut Studio/RED workflow using an offline/online approach and camera raw files. Experienced RED owners who use FCP will be very familiar with this workflow. It’s also clearly described in RED’s FCP whitepaper. On the other hand, if you are about to approach your first RED project and have some trepidation about post, then this is for you. I’ll assume that you didn’t plunk down five grand for a RED Rocket accelerator card and don’t have the budget for a high-end finishing facility using Assimilate Scratch, Quantel Pablo, Avid DS or similar tools. In short, you are looking for the best way to leverage Apple Final Cut Studio and get the most out of your RED files.

Step 1: Download and install the RED Final Cut Studio Installer. This adds the QuickTime codec and the support modules for Final Cut Pro and Color. (The whitepaper is also included in this download.)

Step 2: Copy the RED camera files to your local hard drive array for editing. Back-up the files to other archive media and store in a secure location. (Avoid any illegal characters – like slashes, number signs, etc. – when you label folders.)

Step 3: Start a new FCP project. Use FCP’s Log and Transfer module to import the RED camera files. Set the L&T preferences to a target format of ProRes Proxy. Apply a color preset, like “daylight” if desired or leave “as shot”. This preset will be applied globally to all clips imported in this session.

Step 4: Edit your sequences as you normally would do. If you need to apply certain “looks” to satisfy the producer or client, use the FCP color correction tools for a temporary adjustment. Remember that this is offline editing. The goal is a good rough cut and ultimately an approved, “locked” picture cut.

Step 5: Once the cut is “locked”, use FCP’s Media Manager to generate a version of the final sequence for finishing. Run Media Manager and “create offline” to generate a new FCP project. Set the desired target sequence settings  – most likely Pro Res HQ or Pro Res 4444 (1920×1080 24p 48kHz). Set handle lengths as desired.

Step 6: Open the new media-managed FCP project. Open the Log and Transfer tool. Change the L&T preferences to “native” and “as shot”. Select the master clips (media is currently off-line) and batch capture. The corresponding portions of these RED clips will now be re-imported as native files.

Step 7: Select the final sequence and “Send to Color”. Remember that all of the Color compatibility considerations still apply. Long sequences should be first broken down into shorter sequences. Speed ramps should be “baked in”. In short, do all the usual pre-flight preparation required by the FCP-Color roundtrip.

Step 8: Thanks to the RED Installer, Color has now gained a RED tab in the Primary In room. Camera raw adjustments include gamma, colorspace, temperature, tint, gains, ISO and more. This is similar to making camera raw adjustments to digital still photos in Photoshop. All clips with the native REDCODE codec can be modified by these settings. These changes are on a clip-by-clip basis, but you can copy-and-paste or drag the Primary In settings from one clip to multiple clips.

The rest of the color grading steps follow standard Color operation. Adjust the Geometry settings as desired, render and send back to FCP. There are no raw OLPF (optical low-pass filtering) controls for detail enhancement or sharpening within the RED tab. If you feel that the image is slightly soft, then apply some sharpening within the Color FX room.

It doesn’t really make a lot of difference whether you follow this approach or prep the files first and never return to the native .R3D files. Both methods work and result in great images. It really boils down to what works for you. The process isn’t as hard as people make it out to be. Jump in, test a bit first and then you’re ready to rock!

©2010 Oliver Peters