More about Rainbows
Further questions, extensions, and related atmospheric optics beyond the primary bow.
Once the basic mechanism is clear, the rainbow stops being a single phenomenon and turns into a family of related questions. What changes for the secondary rainbow? How does droplet size affect what we see? Where do atmospheric conditions enter the picture?
These extensions matter because they show which parts of the rainbow are robust and which parts depend on details of the environment or on the optical model.
This post will gather those threads and point toward the broader landscape of atmospheric optics.