Quote Originally Posted by David de Gruyl View Post
They don't, but the hole needs to line up with the ring. I have at least one board that has that configuration and works. I believe it is an actual technika, though. I can't recall if it is off center or on center, but it is one or the other. If necessary, I can check at a later time.
All Linhof boards for the lV and later have the light trap rear raised ring on the back of the board.
All, except for 2 special order Z boards have the hole positioned so that the lens is centered on the film. This places the l
Hole lower on the board.
The 2 Z boards are meant for 240 and longer modern lenses whose rear cell diameter is too large to let the board fully mount onto the front standard due to the rear cell hitting the front standard when mounting.

I am not aware of any Linhof or Linhof copy boards for the IV or later without the raised light trap.

On lll boards there was a round groove on the back of the board that formed the light trap.

Possibly anyone having a Linhof manufactured board without the raised ring has a lll board and not a modern one. All Linhof copy boards are the raised ring type and size.