Pentax 67II vs. 645

David J. Littleboy wrote:

Just thinking out loud, but I'm wondering how it's constructed and how
hard it would be to replace the plain glass piece with another piece of
anti-Newton glass, hence making the need for a mask moot.

You wouldn't want to do that, since that would mess up the image...


If I understand the proposal correctly, that shouldn't be the case?
I do remember the gepe slide mounts with newton glass on both sides:
didn't mess up anything and they were widely used for projecting
dias without the light causing "heat-pop".