Quote Originally Posted by goldie View Post
I don't have any answers, but it sounds like a great idea. Well done.
I have done the same kind of lash up with mine, including the helicoid tube. Theoretically, two stops down from wide open is your best aperture. I like F/11, though.

And I always use my mirror lock up; a heavy tripod, with my camera bag hung from the center standard of the tripod.