It simply amazes me how well modern cameras handle high ISO. I have been working through old slides and seeing how much grain there was not so long ago. I just threw away thousands of Kodachrome frames because as good as they were then, they don’t stand up to the competition from today’s digital images.
So then, why am I photographing this static Bald Eagle at 1/4,000 of a second? Because I am waiting for it to blast-off, and want to freeze the action when it does. There is no noise in the image at ISO 2,500, so why not?