The belief that stops most people
Someone imports twenty minutes of 4K video off a phone, drops it on a timeline, presses play, and gets three frames per second and a fan noise. They conclude their computer cannot edit video and they need a better one. Usually they do not. They need to stop editing the delivery file.
Here is the mechanism, and it is worth understanding once because it explains half of what follows in this course.
The H.264 and H.265 files your phone and camera produce are long-GOP formats. They do not store every frame. They store an occasional complete frame — a keyframe — and then, for everything between, only the differences from neighbouring frames. That is why a ten-minute phone clip is 1 GB instead of 100 GB. It is superb for delivery and terrible for editing, because to show you the frame at 4 minutes 12 seconds the decoder has to find the last keyframe and reconstruct every frame since. Scrub backwards and it does that continuously. Your machine is not weak; you have asked it to solve a puzzle sixty times a second.
Proxies: the single biggest quality-of-life change
A proxy is a low-resolution, easy-to-decode copy of each clip. You edit the proxy. At export the editor silently switches back to the original file, so nothing about your final quality changes.
Every serious editor does this, including the free ones.
- DaVinci Resolve (free): right-click clips in the Media Pool and generate optimised media or proxy media, then toggle proxy use in the Playback menu. Set proxy resolution to quarter or half.
- Kdenlive (free, open source): proxy clips are built in, with a checkbox in project settings to create them automatically on import.
- Shotcut (free, open source, light): a Proxy menu with a single toggle. Shotcut is the one to try first on an old or low-RAM machine — it is far less demanding than Resolve.
- Premiere Pro (subscription, and the name most job ads use): proxies via ingest settings or by attaching them after import.
- CapCut and phone editors handle this invisibly and are honestly fine for short-form.
If you want to make proxies by hand, FFmpeg is free and does it in one line:
ffmpeg -i source.mp4 -vf scale=-2:540 -c:v dnxhd -profile:v dnxhr_lb \
-c:a pcm_s16le proxy.movDNxHR LB is a good cross-platform intermediate: every frame stored whole, so scrubbing is instant, and it encodes on Windows and Linux without the licensing awkwardness ProRes has outside macOS.
The trade is disk space and a one-off wait. A quarter-resolution proxy of an hour of 4K might be 8–15 GB and take twenty minutes to build. You get that back in the first afternoon.
The timeline is a set of instructions, not a copy of your video
This is the second idea that changes how you work. When you drag a clip to the timeline, the editor does not copy the video. It stores a pointer to a file on disk plus a set of instructions: start at 00:04:12:08, run for 3 seconds, at 80% volume, with these colour adjustments.
Three consequences follow, and all three bite beginners.
- Editing is non-destructive. Nothing you do in the timeline changes the source file. You can trim, undo, and re-trim forever. Stop duplicating clips "to be safe".
- Moving or renaming a source file breaks the link. The pointer no longer resolves and you get a wall of red offline clips. Relinking is possible in every editor and it will still cost you an evening. Decide on file names and folders *before* you import.
- The project file is tiny and the footage is not. A Resolve or Kdenlive project is a few megabytes. That matters for backups, which the last lesson comes back to.
Bins, not a pile
The Media Pool or project bin is where an edit is won or lost on projects longer than five minutes. A flat list of 300 clips named C0034.MP4 is unusable by week two.
Make bins before you import: interview, b-roll, audio, music, graphics. Inside b-roll, subdivide by subject or by day, not by camera. Use markers and clip colours to flag the takes you know you want. In Resolve, Smart Bins can gather clips by keyword automatically, which is worth setting up once for anything with more than an hour of material.
The habit that pays most: watch everything once before you cut anything, marking in and out points on the good bits as you go. It feels like a waste of an afternoon. It is the afternoon that makes the edit take two days instead of five.
Where the free tools genuinely lose
Be honest with yourself about this. Resolve's free version does an enormous amount — the full colour page, the Fairlight audio page, Fusion compositing — and it costs nothing, permanently. What it holds back for Resolve Studio (a one-off purchase, around US$295 in 2026, no subscription) includes temporal and spatial noise reduction, optical-flow retiming for smooth slow motion, and several machine-learning features. Output is capped at 4K UHD. That list moves with every release, so read Blackmagic's own comparison rather than any list in a course.
Resolve is also the heaviest of the free editors and wants a real GPU and 16 GB of RAM to be comfortable. On an eight-year-old laptop with integrated graphics, Shotcut or Kdenlive will be a better afternoon than Resolve will.
Today
Take the longest clip you own, generate a proxy, and scrub through both. The difference is the whole lesson.
Before you move on