Today my new DaYi 617 roll film back arrived. It should fit a normal 4x5 Graflok back. But with my Rittreck View I can not fit it. The piece with the rollfilm holder is sitting very tight and the other piece with the groundglass does not fit at all (to wide for the space used by the standard 4x5 ground glass of the Rittreck View).

Before starting to modify I would like to know whether my Rittreck is too narrow or the DaYi is too wide.

Does anybody have (very) accurate measurements of this kind of equipment or knows the Graflok standards?