Celestron XLT series User Manual
Page 19
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Figure 3-3
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Figure 3-2
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The Schmidt-Cassegrain optical system (or Schmidt-Cass for short) uses a combination of mirrors and lenses and s referred
as a compound or catadioptric telescope. This unique design offers large-diameter optics while maintaining very short
to
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he optics of the Advanced Series Schmidt-Cassegrain telescopes have Starbright coatings - enhanced multi-layer coatings on
e primary and secondary mirrors for increased reflectivity and a fully coated corrector for the finest anti-reflection
haracteristics.
side the optical tube, a black tube extends out from the center hole in the primary mirror. This is the primary baffle tube and it
revents stray light from passing through to the eyepiece or camera.
lengths, making them extremely portable. The Schmidt-Cassegrain system consists of a zero power corrector plate, a spherica
primary mirror, and a secondary mirror. Once light rays enter the optical system, they travel the length of the optical tube thre
times.
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