Design Specifications for the TTV camera

The TTV camera set-up must:

1. exclude direct and reflected light hitting the surfaces of the viewfinder and the camera lens [it was accepted that the design might allow a small amount of light from the bottom],
2. be rigid for transport and handling,
3. be reliable, easy to use and produce readily replicable settings,
4. be able to be used hand-held,
5. be tripod mountable,
6. allow the mounting and de-mounting of the viewfinder camera without harm to that camera [as it forms part of my camera collection],
7. permit the mounting and de-mounting of the digital camera without much fuss [as the camera is used in 'normal' photographic life],
8. allow to use both the Nikon D300 and Nikon D80 bodies,
9. allow the use of a range of lenses [it is accepted that some lenses may have a looser framing than the reference lens used (a AF-S VR Micro-Nikkor 105mm F2.8G)], and
10. allow easy access to the focussing ring of the lenses to facilitate manual focussing.
    Ideally, the design would also
11. look reasonably professional and
12. permit to use a range of viewfinder cameras.