－全新 Sky-Watcher StarGate DOB 20'' 主鏡連主鏡座 （光學鏡筒組合，不包括彎月形支架及底座）
－只包括主鏡及主鏡座、副鏡及副鏡座、桁架及調焦座
PARABOLIC PRIMARY MIRRORS 拋物面主鏡
Features High-Quality Parabolic Primary Mirrors to eliminate spherical aberrations inherent in 'fast' focal length reflectors with spherical primary mirrors. The mirrors are parabolized to bring all the light rays to the same focal point to give sharp, contrasty images, which are full of detail.
具有高品質的拋物面主鏡，可消除帶有球面主鏡的"快速”焦距反射器固有的球差。鏡子被拋物線化，將所有光線帶到同一個焦點，以提供清晰、對比鮮明的圖像，這些圖像充滿了細節。
SKY-WATCHER DELUXE MIRROR COATINGS 豪華鏡面鍍膜
Most reflectors today usually have a coat of aluminum as the mirror surface and then an overcoat of silicon monoxide or silicon dioxide to protect it. Silicon dioxide produces a much more durable coat than silicon monoxide but requires specialized equipment to apply it and is, therefore, more expensive. Protection is needed, because, in most reflectors, the mirror is open to the elements and deterioration of the reflective layer reduces the resolution of the telescope. ALL Sky-Watcher reflectors are Multi-Coated with Silicon Dioxide as a standard for Optimum Durability and Long Term Performance.
當今大多數反射器通常有一層鋁作為鏡面，然後是一層一氧化矽或二氧化矽的大塗層來保護它。二氧化矽產生的塗層比一氧化矽更耐用，但需要專門的設備來應用它，因此更昂貴。需要保護，因為在大多數反射器中，鏡子對元素開放，反射層的劣化會降低望遠鏡的解析度。所有Sky-Watcher反射器均採用二氧化矽多層塗層，作為最佳耐用性和長期性能的標準。
