then TAPE it on the back of your camera and see for yourself if
it affects image sharpness.
i have a 4x5/D and for years
i taped a polaroid 545i film holder to the back
and photographed with it. film cost at least 2$ / sheet
so i wouldn't have wasted my time oR money if it affected focus.
and CURRENTLY i have a graphic 23 roll film back (made for a camera with a modern international/graflok back )
it is TAPED on the back of my camera ( series D that like yours takes notched holders )
... i have shot maybe 200 rolls of 120 film with it. my lens is usually
a brass lens with no aperture, or a 210 tessar shot wide open ( 3.8 ) again
it doesn't affect much of anything, at least with my camera and the way i focus.
of course your camera, and your film holder, and tape-job might
give you different results, but it might be a useful experiment for you ...
considering the cost is sheets of paper and some masking tape.
good luck !
ps. feel free to look in my gallery and do a search under "laverne" or series d to see some photos ...
no disrespect intended to the folks who have posted to this thread, they are all know their stuff ...
but often time on discussion boards people talk and talk and talk, but they have never done anything they say they have
and they are just repeating and repeating and repeating what others have repeated to them & i don't want to come off as one of them.