----------------------------------- nobody 10 Iul 2018 16:29 ----------------------------------- @tudor: Producatorul (LZOS) da o metoda relativ simpla de mutare a focusului mai in spate. Each of the Rubinars can easily be adjusted so as to allow deep infinity focusing with either of the extended adapters in place. Since they each make very high quality astronomical photos adjusting them becomes a necessity. They are set at the factory with the infinity stop labeled "W" to go just past the indicating line. The design of the lens however permits this point to be shifted thus moving the focus point a greater distance behind the lens mounting flange. The procedure is simple and does not harm the lens in any way. remove the flexible plastic band around the lens which is normally used for a focus grip. This will expose three small locking screws which can be loosened about one turn each with a find jeweler's screwdriver. The entire focusing ring will then slip off the front of the lens housing. This will expose the adjustable stop mechanism shown in the photo. Loosen the three screws holding the aluminum ring and rotate it clockwise (when viewed from the camera position) about 20mm then retighten the three holding screws. At this point the lens can be mounted to the camera and check for infinity focus in the viewfinder. The correct position is when the lens will focus just past infinity. Place the focusing ring over the assembly, position the "W" at the indicator line and tighten the screws. Replace the flexible plastic focusing grip and the job is done.