I went back to look for eagles again and found that the lake/pond/ditch had frozen over but there were still a couple of eagles milling about and several black birds.
Lessons learned:
- 1/1600 of second still pretty slow for capturing even a big bird in flight.
- ISO 400 is pretty reliable on my camera and darktable matches the noise profile, doing a decent job of noise removal.
- Busy backgrounds are hard to work with but they aren’t show stoppers.
- JPEG is a terrible image format and makes the photos look much worse.