[chickadee]

i usually change iso if am shooting fast moving object ,i go to 400 if need extra light depending on where iam ,sometimes i go 400 on that as well. As i dont understand iso alot ,i play around maybe change it just to see impact.
Unfortunately i cant get 100 iso ,so am stuck with 200iso on lowest.I may be wrong but i sort of look at iso as how i would choose speed of film i would use for film camera.
Great shot ,have taken few like this and like you i didnt change iso ,didnt think i needed to at the time.