ZWO 107mm Quad APO Refractor

ZWO is well known for their superb astro-imaging cameras, but just wait till you get a look at their beautiful 107 mm Quadruplet Apochromatic Refractor! This air-spaced Quad refractor uses a 3 + 1 lens structure that contains two pieces of extra-low dispersion (ED) glass. This produces a flat field so you do not need a stand-alone flattener, which can be expensive! Because there is no need for a flattener, you do not have to worry about calculating its back focal distance in addition to that of the scope and your adapters, making it much easier to add your accessories and start shooting! Of course, the spectacular optical design also all but eliminates chromatic aberration and produces images that are sharp and clear!