The use of a close focus mechanism should be strictly limited to applications where a reference target at long distance cannot be used during the collimation process. A good example would be a maritime application where the gun muzzle is seaboard and must be swung to a target on board the vessel. While collimating, the reference target must be at a long a distance as possible (preferably greater than 800 meters) to insure maximum accuracy. With this being said, the use of a close focus mechanism should be avoided whenever possible. Graflex offers two close focus systems, fixed (12X Telescope only) and removable (8X, 10X, 12X). The close focus mechanisms are designed to minimize parallax normally associated with a focusing at close distances however the end-user must be keenly aware (parallax)to insure maximum accuracy. The slide on close focus mechanisms, part numbers CFM-8000 (8X telescope) or CFM-1012 (10X or 12X telescopes), may be ordered at any time as an accessory. The adjustable focus (PN CFM-RAM) should be ordered as an option and is permanently integrated to our 12X telescope at the factory. The fixed mechanism focuses down to 4.5 meters whereas the adjustable mechanisms focus from 1.5 to 6 meters.