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Sampling Method: DPM++ 2s a RF

Schedule Type: Beta

Steps: 14~20 (16 is the sweet spot)

Shift: 3

CFG Scale: 4

DPM++ 2s a RF will have a slower per-step time compared to Eule a, about 1.5 times, but it can create a very good image in just 6 steps (Schedule Type with Beta)