Trisha Studios Editorial Team
Knowledge Centre
Why Two Stages Exist
The distinction between offline and online editing emerged from practical constraints. In the early decades of digital post-production, workstations could not reliably handle the data rates required for real-time playback of high-resolution original camera files. The solution was to create lower-resolution proxy files — transcodes of the original footage, accurate in timecode and synchronisation but a fraction of the file size — that editors could work with on standard hardware.
The editor builds the creative cut using these proxies. When the cut is locked, the offline edit is 'conformed' — the proxy cut is replaced with the full-resolution originals, producing a high-quality timeline ready for colour grading, VFX, and finishing. This is the online edit.
Storage capacity and computing power have increased enormously since this workflow was established, and in some contexts — particularly short-form content and advertising — editors now work directly with original camera files. But for feature films and long-form content, the offline/online distinction remains standard practice because the proxy workflow is faster, cheaper, and more collaborative than editing in full resolution.
What Happens in Offline
The offline edit is a creative process. The editor works with the director and producer to shape the story — assembling scenes, finding the rhythm of the film, making decisions about structure, pacing, and performance selection. The focus is entirely on the narrative and creative intent. Technical quality is irrelevant at this stage: the editor cuts on proxies that look rough but cut cleanly.
Most offline editing happens in Avid Media Composer or Adobe Premiere Pro. The choice of system depends on the production's workflow requirements and the preferences of the editorial team. Avid is standard on most feature films and high-end series; Premiere is common on documentary and independent production.
The offline process also includes all sound work that is integrated into the creative edit: temp music, sound effects, ADR guide tracks. These audio elements give the film its temporary sonic character and allow the director to evaluate the emotional effect of the cut before the official sound design and mixing process begins.
The Handoff: What Leaves Offline
When the edit is locked, the editor exports an AAF (Advanced Authoring Format) or EDL (Edit Decision List) — a file that describes every cut, dissolve, and effect in the timeline with its associated timecodes pointing to the original camera files. This file is the instruction set for the conform.
The conform technician at the online facility takes the AAF or EDL and uses it to reconstruct the edit from the full-resolution original camera files. This is not as automatic as it sounds — AAF conforming regularly requires manual intervention to resolve discrepancies between the proxy edit and the original files, particularly when mixed frame rates, multi-camera material, or complex effects are involved.
The online facility also receives the full camera originals — either delivered on drives or accessed from shared network storage. The technical quality of the camera originals matters enormously at this stage; any issues with original media (corrupted files, missing handles, incorrect metadata) must be resolved here before the grade begins.
Common Questions
Does offline editing need to happen at the same facility as online?
No. Offline editing typically happens at the production company or in the editor's own facility. Online editing and finishing happen at a post facility equipped for high-resolution work. The AAF or EDL is the link between them. What matters is that the metadata is clean and the original camera files are properly organised.
What proxies should we create for offline?
The standard approach is a 1/4-resolution or 1/2-resolution ProRes proxy transcoded from the original camera files at the point of ingest — either on set by the DIT or at the post facility. The proxy should carry the original file's timecode, scene/shot metadata, and any on-set LUT for reference. Avid DNxHD or Apple ProRes are common proxy formats.
Online Editing and Finishing at Trisha Studios
From AAF conform to colour grade to delivery — our editorial and finishing team handles the full online pipeline.
See Our Editorial Services