Luma Dream Machine (fal)

Luma's Dream Machine was one of the early closed video models that made people sit up - smooth, fluid motion at a time when everything else looked like a slideshow. LumaDreamMachine runs it inside ComfyUI through fal: text-to-video or image-to-video, with start/end keyframes and a loop option. Nothing runs locally; it's a hosted API call in gokayfem's ComfyUI-fal-API pack, billed per clip.

Reach for it when you want that characteristically smooth Luma motion, or when you specifically need a seamless loop or a controlled first-to-last-frame transition.

How it works

You choose a mode, give it a prompt, and optionally supply a start image and an end image. fal runs the generation on Luma's side and returns a URL to the clip. Like the other video nodes here, the output is a string URL - save it before the link expires.

The inputs and outputs that matter

• prompt - describe the scene and the motion.
• mode - text-to-video or image-to-video. In image-to-video, your input image becomes the starting frame.
• aspect_ratio - a generous set: 16:9, 9:16, 4:3, 3:4, 21:9, 9:21.
• image (optional) - the start frame for image-to-video.
• end_image (optional) - the end frame. Set both image and end_image and Luma interpolates a path between them, the same keyframe trick that makes for deliberate transitions.
• loop (default off) - turn it on for a clip that returns cleanly to its start. This is Luma's calling card for social loops and backgrounds.

The single output is a STRING - the video URL.

How to install it

Via ComfyUI Manager: search ComfyUI-fal-API, install, restart. Manually:

cd ComfyUI/custom_nodes
git clone https://github.com/gokayfem/ComfyUI-fal-API.git
pip install -r ComfyUI-fal-API/requirements.txt

No models download. Put a fal API key in config.ini under [API] (copy config.ini.example) or export FAL_KEY=your_key, restart, and find it under FAL/VideoGeneration.

Common issues & troubleshooting

• Auth error. FAL_KEY not set. Fix and restart.
• Image-to-video ignored my image. Make sure mode is set to image-to-video and the image input is connected - the mode switch is what tells Luma to use the frame.
• The loop isn't seamless. Loops work best when the motion is cyclical to begin with; a shot with a strong directional move won't close cleanly no matter what.
• The URL expired. fal result links don't last - route the STRING output into the pack's Save-Media-from-URL utility or download it right away.
• A run fails. The pack raises fal's real error message - content policy, quota, or a bad input. Read it.
• Cost. Every clip is a paid API call. The result cache serves repeat identical calls free (force_rerun bypasses); the spend guard caps a session.
• Windows Portable. Missing fal-client? python_embeded\python.exe -m pip install fal-client.

Luma isn't always the highest-fidelity option next to the newest Kling, but for smooth motion, clean loops, and keyframe control it's a pleasant, predictable node to keep on the shelf.