Perhaps I will give them a call. I currently have a Shen Hao 4x5 which I've had for a few years. I did installed a Fresnel (not specific to the camera) about two years ago and liked the fact that it brightened things up quite a bit. At my age, every little bit helps. Current mounting arrangement is original GG set in the recess with the GG surface facing the lens. The Fresnel is then placed on top of that with the concentric surface facing the smooth side of the GG. I just removed both to examine the recess again. I see nothing that would accommodate putting the Fresnel between the GG and the lens without moving the focus point/film plain. So, barring any additional information I get from a phone call, it seems to me the current order and arrangement is how it would have to be on my Shen Hao. Perhaps later modes were designed differently to accommodate the Fresnel in front of the GG?