The optical tube
The Celestron 8-inch tube houses a 203/2030 Schmidt-Cassegrain optic. The tube is small (length only 50 cm, weight 6 kg) but powerful, making itan extremely good compromise for the mobility-minded amateur. Although the central masking is around 32%, the precision-machined optics compensate for this.
The standard accessory is the company's proprietary StarBright XLT coating, which increases the light-harvesting capabilities of telescopes. When in use, the transmittance of the corrective lens reaches 98%, while the reflectance of the main and secondary mirrors reaches 95%. In addition, the contrast of the image is increased. The basic package also includes a zenith prism, a 6x30 finder scope and a 25 mm Plössl eyepiece with a magnification of 80x.
The optics of Celestron tubes are hand-figured and hand-matched, which means that they consistently outperform the optical quality of competing SC tubes, according to various tests
