Film Holders for 7x17 Folmer & Schwing camera

[Smitty]

Hi All,
I have a Folmer Schwing 7x17 camera and several 7x17 film holders(an original FS 7x17 holder and a couple of different Korona type holders). Question: the Korona holders are different in size which can be dealt with but a bigger question is the difference in ground glass to film plane distance in the holder. The original is spot-on but different distance in the Korona type holders.
Anyone have experience with this type of situation and were you able to resolve?
Thanks, Steve

[Tri Tran]

Hi All,
I have a Folmer Schwing 7x17 camera and several 7x17 film holders(an original FS 7x17 holder and a couple of different Korona type holders). Question: the Korona holders are different in size which can be dealt with but a bigger question is the difference in ground glass to film plane distance in the holder. The original is spot-on but different distance in the Korona type holders.
Anyone have experience with this type of situation and were you able to resolve?
Thanks, Steve

If both holders K&FS are the same thickness then you don't have to worry about it. Just make sure the holder size fits the back perfectly so you wont have any light leak. TT

[LabRat]

Since you have one proper holder, the logical next step would be to measure the depth of it... Put an old negative or piece of scrap film in it, and (preferably) use a depth micrometer to measure from outer holder to film surface, and then compare this to the other holder measurements... You can use a dial caliper's depth rod also, but these rods are considered unreliable for precision work, but you are mainly trying to see if there is a major difference in depth between the master holder and holders in question... There are some very minor tolerances allowed, but you will see if way off...

This should answer your question, and then proceed to plan B if needed...

Steve K

[Jim Noel]

The Korona holders are built for cameras with a slot for the light trap. They have a rounded ridge to fit into that slot. I believe these will need to be sanded off for use in a F&S camera. Also the distance from the flap end to the image area may be different.