I started going out every 10minutes from 8.30pm. Of course, as it got darker the comet got clearer. But it also gets lower on the horizon. It depends on the sort of view you have. My friend in Bayswater is surrounded by trees and her view was impeded by the trees somewhat, and it set very quickly for her. I got to stand on the mulched up stump of one of my pine trees in our front yard and had a terrific view. :~)