SkyWatcher EvoStar 120 / ProED 120 The SkyWatcher S11130 features a doublet apochromatic lens system with Extra-low Dispersion ED glass and Sky-Watcher's proprietary photon anti-rejection Metallic High-Transmission Coatings MHC on all air-to-glass optical surfaces. This combination of glass, lenses, and coatings virtually eliminates chromatic aberrations for clear and bright high-contrast images with true color rendition. This is a versatile optical tube assembly OTA that is well suited for wide-field astronomical observation of prominent nebulae, star clusters and galaxies, or can be used as an astrograph for sky photography, a terrestrial spotting scope or telephoto lens. The larger 120mm aperture of this ProED model not only increases image brightness over the smaller 80mm and 100mm versions, it improves resolution and contrast. ProED 120 Features 4.7 Inch Aperture 120mm 2 Dielectric Diagonal 283x Maximum Magnification Focal Length 900mm, f/7.5 Focal Ratio 8x50 Finderscope Cradle-Ring with Vixen-style Dovetail 2 Crayford Focuser with 1.25 Adapter Proprietary MHC Multicoated Optics Schott BK-7 FPL-53 ED Glass 20 mm 5 mm 1.25 Eyepieces Specifications .boldTbl{ font-weight bold;} .specs td, table.specs th {padding 4px 10px;} Telescope Series SkyWatcher Pro ED APO Telescope Optical Design Refractor Refractor Design Apochromat APO Number of Refractor Elements 2 Telescope Aperture 4.7 Telescope Focal Ratio f/7.5 Telescope Focal Length mm 900 Optical Coatings Metallic High- Transmission Coatings Limiting Stellar Magnitude 12.9 Lowest Useful Magnification 17x Highest Useful Magnification 283x Light-Gathering Power Compared to Human Eye 294x Diagonal 2 Star Diagonal Telescope Eyepiece s 2 Eyepieces Included Finderscope 8 x 50 Focuser Style /