Overview
A stronger upscaling workflow combines an upscaler model with low-denoise image-to-image processing. Rather than enlarging the entire image in one pass, Ultimate SD Upscale divides it into tiles, regenerates detail within each tile, and stitches the tiles back together.
This method can produce substantially finer hair, facial features, armor, and lighting than a direct 4x model upscale. The improvement comes with a trade-off: because image-to-image is generating content, small details can change.