Somewhere I have picked up information (Pentax forum??) that the dioptric correction lens that fits a Nikon F100 (probably others) is a direct exact fit for the Pentax 67 viewfinder bezel? Can anybody shed light on this and advise of actually fitting from F100 to 67 without modification? It seems to me correction lenses for the F100 are more widely available than those for the 67. Ta.