Ever use the tripod socket in the bed of a Linhof Technika 5X7?

[ChristopherMarv]

The position of this thing sure seems dubious to me...

Must be for use with a real heavy lens extended *way* out.

[Delfi_r]

I have used it with the Nikkor-M 9/450 (not so heavy) on portraits. You need to extend all three rails so it's better balanced with the tripod on the bed and not in the normal place. A friend uses it with the Apo-Lanthar 300 mm, a heavy lens.

If I find some photo I'll post