Yes I shoot with both eyes open & I am using a 1/32" yellow clarifier & have a 6 power Tru-Spot lens & have a 9" sight extension, I can see just a little of the blue around the white on a nfaa target. My lens is concaved face me & convexed toward the target.
Try marking your lens so you know where it is positioned in the scope & shoot it at 4 positions, mark at 12,3,6, & 9 oclock & see if your hit move from one side of the target to a different spot. If it does that means that the center is not in the center & I have found this before on several different lens.