As with most compacts, photos are best from the SD980 at ISO sensitivities below ISO 200. At ISO 400, fine detail starts degrading as shots turn less sharp, more smooth, and fuzzy. For a majority of my testing the camera remained in Canon's Smart Auto mode, which was really reliable at picking the correct scenes, but plays things safe by going with higher ISOs. At the two highest full-resolution sensitivities--ISO 800 and ISO 1,600--noise/artifacting and softening from noise suppression are both visible, but the balance is good so all detail isn't lost. However, there is some color shifting and yellowing, which makes shots at ISO 1,600 of questionable use.