I have heard that many of the RB lenses cover 6x8 (some RB cameras are modified for this) But will the lens also cover 6x9 (5,6 x 8,4 cm)? The reason why i ask, is that i have a DIY project in making a 6x9 view camera and i want a lens that just covers 6x9 and not 4x5". for higher performance. I realize that i also need to figure out a method for firing the shutter.