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 | 20,819 | 32,658 | x1.57 |
| training time (optimisation) | 18 min | 73 min | |
| held-out frames (within 0.3 s of a training frame) | 21 (5) | 21 (5) | |
| LPIPS on the fish (lower = closer to the photo) | 0.1294 | 0.1266 | -0.0028 |
| PSNR full crop (dB) | 26.21 | 26.28 | +0.07 |
| PSNR on the fish mask (dB) | 22.86 | 23.16 | +0.30 |
| sharpness ratio render / photo, grain-robust (1 = as sharp as the photo) | 0.489 | 0.482 | x0.99 |
| sharpness ratio, raw | 0.282 | 0.300 | x1.07 |
| sharp match (photo detail reproduced in place) | 0.139 | 0.137 | -0.002 |
| IoU with the SAM mask | 0.877 | 0.874 | -0.002 |
Verdict: same (within noise). LPIPS -0.0028, grain-robust sharpness x0.99 (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: Balistidae 100%, Monacanthidae 0%, Acanthuridae 0% · agreement across crops 100% · 64 crops · bioclip-2.5 (hf-hub:imageomics/bioclip-2.5-vith14, open_clip, zero-shot)

| window | 02:00 – 12:00 |
| visits | 7: 05:01-05:03, 08:09-08:14, 09:03-09:10, 09:17-09:24, 09:41-09:46, 11:16-11:26, 11:47-11:51 |
| frames (10 fps) detected / kept | 432 / 355 |
| valid poses (10 fps) | 394 |
| frames with background plate | 395 |
| median size | 121.0 px |
| 30 fps frames / valid poses | 715 / 594 |
| method | 4D GS, fins + bending + tail (30 fps) |
| model shown | v2 (gs_v2, quality experiment rollout) |
| iterations | 12000 |
| gaussians | 32658 |
| training time | 73 min |
| trainer validation PSNR full / masked | 26.9 / 22.6 dB |
| trainer validation IoU vs SAM mask | 0.883 |
| near-fish band PSNR (fins) | 26.3 dB |
| production status | done |
| visual note (curation) | dark triggerfish with orange tail and orange lines: orange-lined triggerfish, Balistapus undulatus (first guessed Zebrasoma xanthurum) |






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