Confused in SC

oh oh I got this :) thats because it is so close to the objective lens that it is out of focus that it "disappear". On lower magnification say 1x -you can see it as anyone running an AR15 with a red dot will tell you, as you go higher in magnification light "bends" the front sight post get fuzzy and depending on the the magnification usually 3x and up it will appear to disappear. SCIENCE !