Proxy workflow for RAW footage: BRAW, R3D and CinemaDNG without breaking the conform

Why RAW needs proxies at all

A conventional codec like ProRes or H.264 stores finished pictures. A RAW format stores what the sensor saw: a mosaic of single-colour photosites plus the metadata to develop them — white balance, ISO and colour science applied at playback rather than at recording. That development step, the debayer, is the whole appeal (grade from sensor data, change white balance in post, keep highlight latitude) and the whole problem: decoding a frame means reconstructing it, and reconstruction costs GPU time on every single scrub, park and play.

How much cost depends on the format and the machine, but the shape of the problem is constant: a timeline that plays one stream of camera-native RAW smoothly starts dropping frames the moment a second angle or a speed ramp appears. Editing is a rhythm activity — an editor scrubs, parks, plays back three seconds, scrubs again — and media that hesitates on every one of those gestures taxes every cut of the day. The fix has been standard practice since the film era: cut on cheap pictures, finish on expensive ones. In modern terms, edit a lightweight proxy that carries the identity of its RAW master, then switch back to the master for grade and finishing.

What counts as a proxy: codec and bitrate numbers

A proxy earns its keep by being easy to decode, not just small. That rules out the tempting choice — interframe H.264/H.265, which is small but reconstructs pictures from neighbouring frames, precisely what makes scrubbing feel like wading — and rules in the intraframe edit codecs where every frame stands alone:

• ProRes 422 Proxy — the default on Mac-centric pipelines. Roughly 45 Mbit/s at 1080p29.97, call it 20 GB per camera-hour: a full 8-hour shoot day of proxies fits on a cheap SSD.
• ProRes 422 LT — about 100 Mbit/s at 1080p, around 45 GB per camera-hour. Worth it when the “proxy” will double as review media and clients will judge the pictures.
• DNxHR LB — the equivalent choice in Avid-centric shops, at similar orders of magnitude.

Resolution: full HD is plenty for cutting UHD and beyond — half-resolution proxies of 4K+ masters are standard. Two properties, however, are not negotiable. The proxy must keep the master’s exact frame rate — a 23.976 master with a “24 fps” proxy plants the same 0.1% drift described in the frame rate mismatch guide into your own edit media. And it must keep the master’s audio channel count, because some NLEs refuse to attach a proxy whose channel layout differs from the original. Production sound needs none of this: broadcast WAVs are already edit-friendly, and their BWF and iXML metadata should travel untouched.

The identity triple: filename, timecode, reel

Everything that makes a proxy workflow reversible lives in three fields:

1. Filename. Same base name as the master, different extension or a _proxy suffix at most. The name is how humans and relink dialogs find the pair.
2. Start timecode. Identical to the master, to the frame. Timecode is how the NLE knows frame 1200 of the proxy is frame 1200 of the master — and how a finishing conform, months later, pulls the right frames from the camera original.
3. Reel/tape name. Identical to the master. When two cards both contain a C0001, the reel name is the only thing standing between your conform and a wrong-clip relink.

This triple is the contract that lets an edit travel: proxy-cut timelines exported as FCPXML, Premiere XML or ALE reference clips by name, timecode and reel, and the finishing system re-resolves those references against the RAW masters. A proxy with stripped timecode or a blank reel field plays fine today and fails silently at the exact moment the project leaves your machine — the anatomy of that handover is covered in the editor package guide.

Format by format: what each RAW flavour demands

Blackmagic RAW (.braw)

BRAW is partially debayered in camera, which makes it the cheapest RAW to decode — modern machines often cut one stream natively. DaVinci Resolve reads it out of the box; Premiere Pro needs a third-party plugin. That asymmetry is the argument for proxies even when playback feels fine: the proxy plays everywhere, the master doesn’t. Frame rate, timecode and reel metadata are all embedded and survive a Resolve render untouched.

REDCODE RAW (.r3d)

R3D is wavelet-compressed and famously debayer-hungry at full quality — which is why every tool that reads it offers fractional decode quality (half, quarter, eighth). Fractional decode is a fine monitoring trick and a poor proxy substitute: it still burns GPU on every scrub and helps nobody on a laptop without the footage. Both Premiere and Resolve read R3D natively; either can render its proxies. Clip names follow RED’s reel-oriented naming, and the reel name must ride along into the proxy.

CinemaDNG

The awkward one: not a video file but a folder of DNG frames, one file per frame, with audio as a separate WAV beside them. Only some tools ingest it properly — Resolve is the reliable path — and identity handling needs care: the clip “name” is really the folder name, and timecode lives in DNG metadata that a careless transcode discards. Proxy rendering is close to mandatory here; no NLE enjoys scrubbing a 25-files-per-second image sequence.

Canon Cinema RAW Light (.crm)

Canon’s RAW needs Canon’s plugin in Premiere, while Resolve reads it directly. Same pattern as BRAW: native-ish on one system, plugin-dependent on another, so the proxy is the portable copy. CRM carries its timecode and clip metadata internally; a correct render preserves both.

The common thread: RAW proxy generation is a render job in a tool that genuinely understands the format — in practice DaVinci Resolve, Adobe Media Encoder with the right plugins, or Compressor for the formats it covers. The workflow question is not whether to render but who babysits the queue: someone re-entering settings by hand for every card, or an automated round trip that comes back named and stamped correctly.

The render recipe

Whatever drives the render, the settings sheet is short and worth pinning up:

• One proxy per master, mirrored structure — a PROXY/ tree that mirrors the camera folders, so the pairing is obvious to a human at 2 a.m.
• Codec: ProRes 422 Proxy (or LT), full or half resolution, same frame rate as the master.
• Filename = master’s base name. No dates prepended, no version numbers, no “cleaning up” of camera naming.
• Timecode and reel copied from the master — most render tools do this by default; verify once per new camera type, then trust it.
• Audio: same channel count as the master, even if it is a scratch mic you will never use. Attach-proxy features are picky about layout.
• Clean pictures, no burn-ins. Burned-in timecode on a proxy destined for the attach workflow is baked-in noise you cannot remove.

Attaching proxies in the NLE

Premiere Pro: select the masters in the Project panel, right-click → Proxy → Attach Proxies, and point at the proxy files. The Toggle Proxies button switches the whole timeline between proxy and full-res playback; exports always use the masters. If the attach dialog refuses a file, suspect the audio channel layout first.

DaVinci Resolve: right-click clips in the Media Pool → Link Proxy Media, and control usage under Playback → Proxy Handling. Resolve can also generate its proxies from the same menu — convenient when Resolve is already your RAW renderer, and the result lands with identity intact.

Final Cut Pro: manages proxies internally, generating ProRes Proxy copies inside the library, and since 10.4.9 can relink externally supplied proxy files. The identity triple matters just as much here — FCP’s relink matches on the same fields.

Cutting proxies changes nothing downstream: the timeline references resolve back to the masters at export or conform, provided the triple held. That is the entire trick.

Fail modes: how good proxies go bad

• The renamed proxy. A well-meaning “tidy” rename pass — dates, scene numbers, initials — breaks the filename half of the contract. Relinking becomes archaeology.
• The stripped timecode. Consumer transcode tools and watch-folder scripts that default to “start at 00:00:00:00”. The edit works; the conform doesn’t. Nobody notices for weeks.
• The wrong-rate proxy. A 23.976 master rendered to a 25 fps proxy — or vice versa — drifts against its own sound and cuts on frame boundaries the master doesn’t have.
• Interframe “proxies”. H.264 at low bitrate is half the size of ProRes Proxy and scrubs like syrup, which defeats the reason proxies exist.
• Duplicate reel names — or none. Two cards, both A001, or a renderer that leaves the reel field blank. The conform picks a clip; occasionally the wrong one.
• Proxies of the proxies. When review copies get cut instead of the identity-carrying proxies, generations multiply and the path back to the master quietly disappears.

Where Launchr Post fits

Launchr Post treats RAW proxies as a round trip rather than a manual render job. When it ingests a shoot day and meets masters that cannot be proxied directly — BRAW, R3D, Canon CRM and friends — it drives your own tools (DaVinci Resolve, Adobe Media Encoder or Compressor), hands them exactly the settings above, and collects the finished files: same base name, same start timecode, same reel, mirrored folder structure. Proxies you already have are recognised and reused instead of re-rendered, the full-resolution original stays one click away from every clip, and the editor package that leaves the app references masters and proxies that agree about who they are. Everything runs locally on your Mac.