Today I have been at the local camera store that are about to shut down.
I asked if they had a Schneider Kreuznach IIIB filter for my 90mm lens that
I use for the 6×17 camera, THEY HAD!!!!
And I got it for 110 Euro!
I’m rely looking forward to try it out.

/Stefan

Camera tested with the center filter by my friend Leif.
http://www.stockholmviews.com/diyphotogear/diy_6x17_camera5.html