There's a difference between a "view block" and a "scene divider" in my mind. A view block is something I would use to blot out a water heater or some other non-layout thing. Or, it's there to isolate a part of the layout, such as a staging yard, a helix or some other feature that's functional, but not necessarily a part of the scenery.
My definition of a scene divider would be any device that's employed to separate scenic vignettes within the layout. This could range from Ed's stand of trees, to my 12" skyboard, to a structural wall in the house that separates the yard and the city from the mountains and prairies.
The height of it don't enter into it. If you want it to be at eye level, or to completely obscure another part of the layout to propagate an illusion of distance, that's fine. In my circumstance (and maybe yours) the scene divider is low for a number of reasons. First and foremost, it was the material I had at hand. But it works for me because:
A) The peninsula juts out into the center of the room, and there's a ceiling fan directly above it. Too much height, and I wouldn't be circulating air the way I need to.
B) In the summer, I use a window rattler air condition unit. A tall scene divider (and therefore no ceiling fan) would make it impossible to circulate air up there efficiently.
C) I like to have a crew over now and again to run trains. Having a low sky board makes it easier to see what's going on on either side of it, and makes chatting with the crew unimpeded by visual obstacles.
As I noted, the main thing I wanted was a "backstop" for the scenes on either side, and enough sky to work with low angle photos. Too much height would not accomplish any of the above goals.
Lee
