Both the varizone [32 mm] and the Lumizone [40 mm] are 2.5xX4x variables. The numbers on the speed rings get you close but are not absolute like a chrony is. Arrow construction doesn't matter much, it's the fps that along w/ weight determines the trajectory, which they both do a great job compensating for, imho. You don't have to change any settings unless you change arrows weight or speeds.Add fletching type for the purists, lolFor plinking at ranges past 50 yds w/ conventional sight in, I've found it easier to hold the 50 yd triangle on target, and pay attention to where the aim point above it is and then hold the 50 yd one there.

Smoke and I were at a dot shoot [unknown distance] this fall. My Leupold goes to 60 yds [aim points] Once I figured the target was 80 yds [81 actual] I rested my Phoenix and put the 60 on the dot and made a reference in my mind where the 40 was at above the dot, then held the 60 there and did amazingly well, missing a 3" bull by fractions of an inch twice, offhand. First I got smart too late then lucky, lol.