Ken Hart wrote:

That 8 minute exposure kind of threw me when I first saw it. I have
photos of a full moon, that I shoot using the "Sunny-16" rule (shutter
speed equals ISO, Full sun= f/16, etc.) at around f/5.6 or f/8.

I was guessing that a "blood moon" would be a couple or three stops down
from the light of a full moon.

It varies hugely. Helen Hogg, in "The Stars Belong to Everyone" says
that there have been at least three cases when the eclipse was dark
enough that the moon disappeared entirely. (In two cases this seems
to have been connected to volcanic dust in the atmosphere, but in the
most recent case on June 10, 1816 that does not appear to have been
the explanation. At other times total eclipses of the moon have been
particularly bright, for instance in the eclipse of March 19, 1848,
the moon was so bright that many persons doubted that the moon was really
in eclipse. (see pages 112-113 of The Stars Belong to Everyone).

Peter.
--