To me in this context ordinary film would mean unsensitized film, thus blue-only sensitive.
To achieve that a blue color-seperation filter would be best.
As you are busy with large format a X-ray film of the unsensitized kind could be an alternative if at hand.
If the film is unsensitized it will not record light at all.
[FONT=Comic Sans MS]Films NOT Dead - Just getting fixed![/FONT]