Interesting answer. On the Grafloc back there are Graflex sliders. You can't use it under the spring back, but can you use it with the spring back removed?
tim in san jose
just tried using a slotted 4x5 holder on my speed graphic with a grafloc back ..
the holders are "an edge" ( 1/8" ? ) too large
AND they don't have that bead that locks a modern
film holder into place .. you know, the ridge
near the top of the holder that keeps the light out.
it seems that the graflex/slotted holders are a
different system/different beast altogether.
john