Hyperfocal distance is the distance at which you need to focus a lens at any given aperture to achieve maximum depth of field from near to infinity. (Not Here To Eternity
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If you photograph a landscape with mountains in the far distance and little snowdrops in the foreground 3 feet from the camera, and you want both to be in focus, then you select a very small aperture for maximum depth of field. It's no good obviously, focusing on either the mountains or the snowdrops. DOF extends both forwards (towards you) and rearwards from the point at which you focus, and is greater the further you focus away from the camera.
Too bring the mountains and snowdrops both into acceptable focus we need to focus at a point in the mid distance such that when we take the shot and the lens stops down to the selected aperture, DOF extends from the snowdrops to the mountains. The distance we've focused on to achieve this maximum DOF is called the hyperfocal distance.
There used to be very handy depth of field scales on lens barrels to aid with setting hyperfocal distance. Sadly they've now disappeared and we have to rely on the depth of field preview button to stop the lens down before we take the shot and see the effect of the selected aperture on DOF. The downside is because we look through the lens, the viewfinder becomes much darker when using the DOF preview button.
Because Sammy has finely focused on a given point on his test chart, that point should be rendered sharply regardless of the aperture used so I can't see that the hyperfocal distance comes into it at all. It's a bit early in the morning for this, but thanks Spencer!