As a low hours pilot judging height is something I'm still struggling with. It's judging the height to flare at that gives me problems as I often flare too early. What helps me is to think of the change in perspective, and the change from looking down at the runway to looking along it.
When I look along the runway rather than down at it I can't help but flare. For me waiting for the end of the runway to disappear from view as I look down it before starting to flare is the most helpful as it seems to work on all runway widths, but I suppose It won't work for a sloping runway
