For example, with a typical Leupold brand duplex 16 minute of angle (MOA) reticle (of a type as shown in image B) on a fixed-power scope, the distance from post to post (that is, between the heavy lines of the reticle spanning the center of the scope picture) is approximately at , or, equivalently, approximately from the center to any post at 200 yards. If a target of a known diameter of 16 inches fills just half of the total post-to-post distance (i.e. filling from scope center to post), then the distance to target is approximately . With a target of a diameter of 16 inches that fills the entire sight picture from post to post, the range is approximately 100 yards. Other ranges can be similarly estimated accurately in an analog fashion for known target sizes through proportionality calculations. Holdover, for estimating vertical point of aim offset required for bullet drop compensation on level terrain, and horizontal windage offset (for estimating side to side point of aim offsets required for wind effect corrections) can similarly be compensated for through using approximations based on the wind speed (from observing flags or other objects) by a trained user through using the reticle marks. The less-commonly used holdunder, used for shooting on sloping terrain, can even be estimated by an appropriately-skilled user with a reticle-equipped scope, once both the slope of the terrain and the slant range to target are known.