Much ado about image grain.

[Loupey]

Here's an example of what I had in my mind for several years but couldn't execute until high ISO performance caught up:

A shot during a rain storm (it gets dark you know) and the ripples/drops move very fast when shooting close up. If I could have gotten a clean shot at ISO 3200/6400 I would have (I wanted more DOF on this shot).

Anyway, I shot it at ISO 1600 and this image is cropped. No way possible to capture this in the field at ISO 100~400. EXIF attached.