More clear image; APO astro camera lens consists of a 3-group 5-piece petzval objective lens structure; which includes a set of triplet lens; bringing you a clearer image 44mm full-frame; APO telephoto lens avoids aperture blocking; whether mirrorless camera; SLR camera; or deep-sky camera; you can photograph clear image without trouble Convenient operation; SV555 telescope camera lens is equipped with an accessories for EAF (not included) for automatic and accurate focus; you can get an accurate angle to photograph quickly and conveniently Single-speed focus; the telescope camera lens supports fine adjustment; enabling you to adjust the photography angle accurately for fast shooting Various aperture range; the astronomical photography lens can adjust the aperture from F22 to F4.5; meeting a variety of use needs; the included graded adjustment ring and scale also make it convenient for photography by preventing accidental touching Compatibility; SV555 telescope camera lens features an M48x0.75 filter thread to install the 2\" filter; additionally; the V-style & Arca-Swiss quick-release system is compatible; flexible and easy to use; enhancing the efficiency Convenient to use; the APO astro camera lens is featured with a handle; bracker; and dovetail plate; making it more convenient to use the lens when shooting