Double Separation Lens for 90mm Refractive Astronomical Telescope (1 piece) - Multilayer Treatment Available(D90F900 Green Film)

Optics: The D90mm dual separation lens delivers an outstanding image with a combined focal ratio of 1/4 to 1/8, ensuring clear and accurate astronomical observations. Versatile focal length options: Choose from three focal lengths (500mm, 650mm, or 1000mm) to meet your specific astronomical observation needs, enhancing your stargazing experience. Multilayer coating: Available with green or blue multilayer coatings, these lenses minimize light reflection and maximize light transmission for brighter and sharper images. Precision Engineering: With strict tolerances for diameter (+0/-0.12mm), center thickness (±0.2mm) and focal length (±0.1%), these lenses are designed for optimal performance in refractive telescopes. Easy DIY Assembly - Designed to be compatible with various astronomical telescopes, this lens kit allows for simple assembly, making it perfect for amateur and experienced astronomers.