I'm actually looking more at close range. They put AOs on rimfire scopes, and set the parallax at closer ranges for muzzleloaders, shotguns, rimfires and crossbows. I'm looking into using a fixed power rifle scope on my crossbow. It currently has a red dot mounted that came with the bow and is touted at being parallax free. Well i can tell you that from looking through it at a target at 20 yds it seems to be parallax free or adjusted when you move your head side to side, but when you move your head up and down it is all over the place. Obviously cheek weld is most critical with this sight. So, my question is then, how much parallax error will there be at 15 to 30 yds with a rifle scope with a parallax set at 100 yds. I want a fixed power because weight is also an issue with crossbows already being somewhat heavy I'm not interested in any of the scopes from the crossbow manufacturers. Too many aiming points on most and i don't need it illuminated. And they don't publish the specs on any of them i.e. eye relief, etc. I'm trying not to have to go to the Leupold custom shop but it looks like that is what i'm going to have to do unless i can find something else.