gs_final, 4000 iterations) with 12000 iterations and a gaussian cap of 100,000 — the only change of the quality experiment that passed its review. Other changes (frame selection, water and motion-blur models, white balance, lossless crops) did not. The two turntables play in sync (same orbit and timing).
| metric | v1 gs_final | v2 gs_v2 | change |
|---|---|---|---|
| iterations | 4000 | 12000 | |
| gaussians | 46,076 | 85,709 | x1.86 |
| training time (optimisation) | 18 min | 73 min | |
| held-out frames (within 0.3 s of a training frame) | 24 (9) | 24 (9) | |
| LPIPS on the fish (lower = closer to the photo) | 0.2143 | 0.2035 | -0.0108 |
| PSNR full crop (dB) | 21.85 | 21.99 | +0.14 |
| PSNR on the fish mask (dB) | 17.15 | 17.36 | +0.22 |
| sharpness ratio render / photo, grain-robust (1 = as sharp as the photo) | 0.491 | 0.479 | x0.98 |
| sharpness ratio, raw | 0.398 | 0.417 | x1.05 |
| sharp match (photo detail reproduced in place) | 0.366 | 0.308 | -0.058 |
| IoU with the SAM mask | 0.885 | 0.872 | -0.013 |
Verdict: better. LPIPS -0.0108, grain-robust sharpness x0.98 (not sharper). Differences below 0.0034 LPIPS or x1.12 sharpness are within the run-to-run noise of training.
Held-out frames: fixed per fish (work/quality_exp/<fish>/heldout.json), evaluated identically for both models (test-time fit of pose, colour and bending with the gaussians frozen). Both models were trained on all frames of the same data set, so held-out frames near a training frame favour both equally; this is a like-for-like comparison of the two recipes, not a generalisation test.
Family: Chaetodontidae 100%, Pomacanthidae 0%, Serranidae 0% · agreement across crops 100% · 64 crops · bioclip-2.5 (hf-hub:imageomics/bioclip-2.5-vith14, open_clip, zero-shot)

| window | 12:00 – 22:00 |
| visits | 12: 14:12-14:14, 14:17-14:25, 14:30-14:32, 15:20-15:22, 15:44-15:49, 16:28-16:37, 16:44-16:46, 16:49-17:04, 19:43-19:54, 20:13-20:20, 20:23-20:23, 20:44-20:47 |
| frames (10 fps) detected / kept | 695 / 550 |
| valid poses (10 fps) | 394 |
| frames with background plate | 584 |
| median size | 129.0 px |
| 30 fps frames / valid poses | 720 / 463 |
| method | 4D GS, fins + bending + tail (30 fps) |
| model shown | v2 (gs_v2, quality experiment rollout) |
| iterations | 12000 |
| gaussians | 85709 |
| training time | 73 min |
| trainer validation PSNR full / masked | 22.2 / 17.7 dB |
| trainer validation IoU vs SAM mask | 0.865 |
| near-fish band PSNR (fins) | 24.4 dB |
| production status | done |
| visual note (curation) | crown butterflyfish, Chaetodon paucifasciatus likely |






point_cloud.ply (canonical 3D gaussians) · poses_refined.json · model.pt (incl. per-frame 4D params) · species.json · previous version v1: gs_final point_cloud.ply