I made this photograph during civil twilight one evening.
are three different types or stages of twilight and these occur at
pre-dawn and post-sunset periods of the day. In the morning
'astronomical twilight' starts about one and a half hours before
sunrise. Then comes 'nautical twilight' which occurs about one hour
before sunrise. Finally, for about half an hour before sunrise, there is
the period known as 'civil twilight' and it is during this last period
that great light for photography can occur. I say 'can' as great light
can never be guaranteed but for me sometimes that doesn't matter as then
landscape photography can become more about trying to convey a sense of
being somewhere rather than just recording a scene in great light.
Sometimes even a great sunset can detract the observer from the beauty of a location!