Most of the SP-570 UZ's photos in the middle to long end of the zoom range start a bit soft, so detail degrades fairly quickly as you increase ISO sensitivity. For this type of shot (taken at about 38mm-equivalent), I probably wouldn't go higher than ISO 100; it gets quite blurred at ISO 200, and by ISO 400 starts to look overprocessed, albeit with little visible color noise. Also note how the color sifts slightly as you change settings.