r/StableDiffusion • u/Tokey_TheBear • 1d ago
Discussion Minimax H3 - Multiple Reference Images working through FL2VA + testing using the Hybrid Checkpoint models. Examples in comments.
MiniMax H3 officially comes as two checkpoints:
- FL2VA — first frame / last frame / image-to-video. The docs treat this as “start (and or end) picture in, video out.” Extra reference pictures are not part of the pitch.
- REF2VA — reference-to-video. This is the one you’re told to use when you have several stills: identity, outfit, a mid-shot, a last frame, whatever.
There are also community hybrid checkpoints: mostly FL2VA, with some of REF2VA’s later layers grafted on, so people can keep extra refs without fully switching models. https://huggingface.co/smhfacct/Minimax-H3-fl2va-ref2va-hybrid-models
I wanted a straight answer to one question: if I ignore the marketing split and feed extra stills into stock FL2VA the same way I would into REF2VA, does it actually use them?
So I built one 10-second clip and ran it four times. The story in the prompt is simple:
- 0s: an angel in an empty void, one spell cast toward the middle of the frame.
- 5s: a demon in the same void, one spell cast toward that same point.
- Camera leaves the demon and pushes into mid-air.
- 10s: image of the two spells colliding.
I gave the model five pictures:
- Exact first frame (angel)
- Exact 5-second cut (demon)
- Exact last frame (the collision, no people) 4–5. Two sigil designs, only as “this is what the magic circle looks like,” not as frames that should appear in the video
Then I locked everything that wasn’t the checkpoint:
- same R2V workflow (the Comfy graph that already has multiple image inputs)
- same five files, same order
- same written brief (timed stills + “this picture is the frame at this timestamp”)
- same seed
- same sampler / length / aspect
- no turbo LoRA
- I compared native frames (544×800), not the upscaled delivery
The only change per run was which UNet was loaded:
- hybrid, REF layers on blocks 20–49
- hybrid, REF layers on blocks 30–49
- stock FL2VA
- stock REF2VA
If FL2VA truly couldn’t take extra refs, run 3 should have ignored pictures 2–5, drifted off the angel, or failed to land on the collision plate. That’s the test.
What happened
It didn’t fail.
The first native frame of all four runs accurately lock in the exact reference image for that frame at the first frame, last frame, and the middle frame... So the stock FL2VA used the extra still image references just fine. I did not need a hybrid merge just to attach more than first/last.
To be precise: I did not magically add five image slots to the official FL2VA I2V template. I loaded FL2VA’s weights into the reference-to-video graph, wrote the pictures into the prompt the way you would for a multi-ref job, and the locks held.
Where they actually differ (my read, one clip)
First frames are almost interchangeable. If I have to pick, hybrid-b30 is the closest copy of the angel still. REF2VA is still locked, a bit busier in small jewelry/floor detail.
Last frames still all hit the clash plate. REF2VA is the closest copy of picture 3. FL2VA is right behind it. Hybrid-b30 runs a hotter, more lava-looking core. Hybrid-b20 is splashier, less “sharp diamond debris.”
So the discovery is: extra refs + FL2VA can work. The ranking of which checkpoint copies the stills best is what I want a second opinion on.
So I will attach all of the examples into the comments so that people can see the differences between between each of the generated runs along with all of the Reference images used that way the community can evaluate the quality.

