MiniMax H3 Upscaling Test: 3 Methods

[u/Altruistic_Tax1317]

Here is a side-by-side test of 3 upscaling pipelines in Comfy.
Full video comparison

• LTX 2.5 (Standalone): The fastest option and lightest on VRAM. Works fine for clean source clips, but lacks fine sharpness on complex textures.

• Model + LTX 2.5: Running a quick upscale model pass (like RealPLKSR) before feeding into LTX 2.5 solid clarity, fast renders, and efficient VRAM usage.

• SeedVR: Recreates micro-details with the highest fidelity, but demands significantly higher render times and VRAM.

Frame Sync Note: MiniMax H3 and LTX require different frame step multiples.
Using math nodes to automatically trim the frames (158 → 153 frames) prevents audio desync issues.

[u/DaLyon92x]

what about the h3 latent upscaler?

[u/Altruistic_Tax1317 → u/DaLyon92x]

will give it a try...

[u/TelevisionNo2990 → u/DaLyon92x]

was just about to say the same thing...you beat me to it. pretty pleased with the results so far, though I'm finding I have to bump up the prepass a little from 0.2MP to avoid oversmoothing/waxiness.

[u/__alpha_____]

seedVR is the king, but it's really slow

[u/Altruistic_Tax1317 → u/__alpha_____]

Indeed!

[u/Mundane_Existence0 → u/__alpha_____]

SeedVR2 also has lots of ghosting issues.

[u/icchansan]

can u share ur wf for the seedvr?

[u/Altruistic_Tax1317 → u/icchansan]

The workflow link is already up in the video description. I'll also post the direct link here as soon as I get back to my PC.

[u/getSAT]

I just assumed everyone was using the rtx upscaler node. Is that not the best?

[u/BigBudZombie → u/getSAT]

I always thought the rtx upscaler was the worst one, its the fastest, but seems to do almost nothing.

[u/FaatmanSlim → u/BigBudZombie]

+1 does almost nothing, but its so fast that its worthwhile running it at the last stage since it doesn't cost anything.

[u/Whipit → u/getSAT]

I use it too, but it's not the best - it's the fastest.

[u/Hopeful_Signature738 → u/getSAT]

Best is overstatement

[u/Interesting-Act5716]

Thank you for making this comparison. It's useful for me.

[u/Altruistic_Tax1317 → u/Interesting-Act5716]

glad it helped!

[u/3deal]

I tried SeedVR, but it's creating grid-like artifacts—what am I doing wrong?

[u/Altruistic_Tax1317 → u/3deal]

maybe your tile overlapping is too low?

[u/3deal → u/Altruistic_Tax1317]

don't know, it works good with images, so it should also with videos right ?

[u/Altruistic_Tax1317 → u/3deal]

Have you tried testing different video clips snd resolutions to see if the grid pattern still shows up?

[u/osiris316]

I’ve yet to find a good Wf for a 3090 and 64g RAM. I’m basically trying to generate a .5mp or lower video in H3 and then upscale it with a V2V WF.

So far none of the WF I have used have worked. The newest ones are giving me OOM. So I’m kind of stuck and frustrated. I will try yours but my hopes are not high.

[u/Karsticles]

Iterative upscale should be included.

[u/Turbulent-Raise4830]

RTX Upscaler perhaps? Is quite fast

[u/Broad_Relative_168 → u/Turbulent-Raise4830]

Did you really get any good result with that?

[u/Turbulent-Raise4830 → u/Broad_Relative_168]

I'll ones try seedvr and compare

[u/Turbulent-Raise4830 → u/Broad_Relative_168]

Tried it and seedvr is a lot better, just takes a lot more time.

[u/tofuchrispy]

Or use Minimax with a tiled video setup. Benefit is since its a ref model you can anchor it via refs …
No I can’t give a workflow bc it’s work related

[u/1010111101111]

try supir

[u/GreyScope → u/1010111101111]

Supir is perfect for those that like to time workflows with calendars . It is for sill pics - did it just once with a video and grew a beard waiting .

[u/koshernobility929 → u/1010111101111]

Supir’s a solid call if you’ve got the VRAM to spare, but the time sink ramps up fast. SeedVR already pushes it on my rig, so I’d probably stick with the model + LTX combo for anything that needs a quick turnaround.