Rob, wouldn't you need the backdrop to extend over the floor?
In the ideal world of the old studios I had, yes. In this current one, no; the reason, really, is that I'm more interested in getting into portraiture than anything else - from waist upwards holds most of what I think I'd want to shoot anymore. What I still want to find is an old bar stool on which I can perch my victims and prevent them from wandering off sideways or back 'n' forth... Apart from the fact that plastic core tubes were only available in the local hardware store at a maximum length of two metres, that's also partly why I didn't go for the whole width of the available hanging space, even though I think I could have found longer pipes in one of the plumbers' shops.
Ain't going to be shooting any fashion and nudes etc. for which latter I'd rather have worked on the beach or in an olde worlde bedroom with four-posters and mosquito nets etc. than on a soulless white roll. I really would want to tell a little story rather than just make a body shot.
If I do have to do a full length for some reason, an old sheet on the floor and some PS and it's done. Actually, the old white sheet thing can come in useful as an alternative to using the brolly on my studio flash (if it still works!): the sheet can be hung over the support for the sunshade on the left of the backdrop and a flash banged through it. Or off the ceilng - all sorts of options as long as it's black/white: so much colour bounces off the floor tiles that it would be very difficult to keep things neutral.
Actually, it was with this portrait thing in mind that I'd had the fleeting idea of the square 'blad negative rebate... lost interest in that now, though; seems a pointless additional effort.
Interestingly, I note that the shot with the roll hanging down gets more viewings than the support system shot above it which, I'd thought, was of greater interest in the scheme of things... I'll have to make another shot to replace the hanging, open roll one by pasting a girl onto it...