The more megapixels the camera sensor has,,the more forgiving higher iso. New cameras can have outrageous iso. Lens that do well in low light also help with the iso, I think. Most newer cameras do handle well from 100-800 but you can play with it to see how your camera functions. Programs like Lightroom can deal with pixelation but I don't have that program nor do I know how it is done, just have read about it. I have photoshop elements but I don't know if it has a correction in it.