The DG-80 WC Focusing Screen for 645D and 645Z Cameras from Pentax is a Cross-Lined gridded, matte field focusing screen to fit the 645D and 645Z medium format digital cameras. The screen is an alternative to standard screen and features a center circle with three horizontal lines and five vertical grid lines.
Focusing Screen IS FINE, but metal tweezers is horrible . I try to remove old screen using them and ....scratch ,thanks god only old screen.New screen i am install easily with my bare fingers. DO NOT use metal tweezers,to avoid damage your new Focusing Screen. NEW one is good and comfortable to use,greed lines really helpful .
Helpful to me to keep the lines straight. Also helps me with my focus. As my eyes age - it gets harder to make sure the focus is accurate. The additional lines work great for that.