It was trained with 640*640.
It was confirmed that it works well in 640*768 full body shot.
Since it is unstable, I share the settings I tested.
Sampler: ++sde karras
steps : 40
upscale step :30
640*768
CFG: 20
use After Detailer
use DT
usefull prompt: <lora:badbroIrezumi:0.8>, tattoo, Irezumi, (full body:1.5), (wide shot:1.3), (depth in field:1.3), (simple white background:1.3)