This photo was actually somewhat of a mistake. I was taking a series of 'bracketed' photos - each with different shutter speeds - in the hope of merging them together afterwards, to show more detail of the corona. But I forgot to turn off my camera's 'auto-ISO' feature, so each shot ended up getting taken with an ISO larger than I wanted. This photo (the best-looking of the set) was taken at 1/1000s, but with the camera's maximum ISO of 25600. That's why there's so much 'noise' in the image. But I was able to clean most of that up; here's a version with the noise removed