Astro Edition adapter are specially designed for wide-angle and space astrofotography telescopes. The 48 x 0.75 mm thread side is screwed onto your wide-angle telescope and the camera's bayonet side can be safely attached to your mirrorless camera as if it were a native lens. The supplied extension tube is used to focus on some telescopes that could cause problems to set the focus far enough away. The extension tube is removable and releases a secondary 48 x 0.75 mm interior thread for telescopes that focus close enough on the mirror or installed a Barlow lens. The imperfections and aberrations of older lenses are exactly the strengths that distinguish them from modern lenses. In addition, a full-mechanical lens is likely to be repaired longer and cheaper than modern focus-by-wire lenses.
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