A frozen FID reference for text-to-image models trained on BLIP3o-256: 50k real (image, caption) pairs sampled from the training mixture (journeydb 5,903 / long-caption 37,518 / short-caption 6,579), per-shard reservoir sampling over 102 randomly chosen shards, seed 2026. Protocol: generate one image per caption in prompts/val/ (50k total), then compute FID against referencestats.npz. Only compare runs with the same prompt count. The shards are a subset of the BLIP3o pretraining data (BLIP3o/BLIP3o-Pretrain- on the Hugging Face Hub); see that release for the original licenses and terms.