This model was mostly trained on 512x512 so you should stick to approximately that size. Use external upscalers like RealESRGAN, SwinIR or BSRGAN or GFPGAN (fa

This model was mostly trained on 512x512 so you should stick to approximately that size. Use external upscalers like RealESRGAN, SwinIR or BSRGAN or GFPGAN (faces). Alternatively use hacks like txt2imghd to get it to natively create 1 MP images.