Calumet 120 holder & infrared?

[walter23]

I note in the calumet c2n instructions it says something about the holder not being appropriate for infrared. Anybody tried it? Is the plastic material not IR opaque?

 

[glbeas]

I tried the 6x12 holder with Konica 750 and it was not good. I was able to swap the plastic darkslide out for metal but the major leaks were the seals at the hinge. The older metal 6x7 ones seemed to work just fine.