H3 Studio Film

Most film-joining nodes make you run the render first. H3 Studio Film takes the opposite approach: it assembles the film from the takes that already exist on disk, with no loop and no sampling at all. Queue it and it's back in a couple of seconds.

What it hands you

Every scene's current take - its latest render, or the take you made current in the Renders panel - joined the same way H3 Studio Join does, with continuations crossfaded. A scene that has never been rendered plays as black for its length, and the console names it, so the film keeps its timing instead of silently contracting.

The studio already saves the film after a full render, and Renders ▸ Export film saves one at any time. So why exist? Two reasons the author gives: put a score under it, or feed it on into a graph.

Inputs and outputs

Required, all three of them, though they have sensible defaults: crossfade (frames each continuation fades in over, 0–39, default 8), music_volume (default 0.8), music_fade (seconds the score fades out at the end, default 2).

Optional: link, the studio this joins, which you pick from the node's dropdown - the docs say to pick it rather than wire it, and with only one studio in the workflow it's chosen for you. And music, an AUDIO input for that score.

Output is a single video. Wire it into Save Video, same as any other video node.

The bit worth knowing

Its fingerprint_inputs returns the modification time of the studio's scenes file, with a comment explaining why: "A new take changes the film without changing the node's inputs." So the node re-runs whenever a scene gets a new take, even though you never touched a widget. Nice touch, and the reason a "why did that re-run?" question here has a good answer.

Typical use

Its own small workflow, or sitting beside your render loop with the loop's nodes bypassed - so you're not competing for VRAM while 12 scenes sample. Render the film, then come back and run this to lay music under it.

cd ComfyUI/custom_nodes
git clone https://github.com/Nynxz/ComfyUI-NynxzH3

Restart, ComfyUI 0.30.0+. Nothing extra for this node.

Gotchas

Half your film is black. Those scenes haven't been rendered yet - which is exactly what it's telling you, per scene, in the console. Head back to the studio and render them.

The music doesn't appear. music is optional, so an unwired socket is silent, not an error. Also check the studio's own music field is empty: the docs suggest leaving it that way, so H3 doesn't write its own score into every scene and fight the one you're laying over the top.

Crossfades look wrong. crossfade can only fade in over the frames a continuation actually carries (up to 39). Set higher than what a scene has and there's nothing to fade with.