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Using a 12 1/2-inch f/4 Newtonian reflector and the T-threaded interface ring, the author experienced strong vignetting in this image of NGC 4565 that could not be corrected with flat-field calibration.
Newtonian reflectors from the 1960s and 1970s can be excellent if the mirror coatings are still in good shape.
An altazimuth variation that's popular on Newtonian reflectors of all sizes (from $200 starter scopes to 36-inch monsters) is the Dobsonian mount.
The popular f/10 Schmidt-Cassegrain requires focal lengths of 10 to 5 mm, while the increasingly common "fast" f/5 Newtonian reflector needs 5 to 2.
This photographically fast Newtonian reflector is built around a 150-mm parabolic primary mirror manufactured from B270 glass that reaches thermal equilibrium quickly.
This turned out to be a 10" Newtonian reflector on a Sellers mounting, a very substantial instrument in those days.
5-inch (114-mm) Newtonian reflector uses a corrector lens in its focuser, thereby permitting a long focal length of 1,000 mm (f/9) to be packaged into a tube only 18 inches long.
His 20-hour cumulative exposure using a home-built 16-inch Newtonian reflector and CCD camera identifies objects down to magnitude 24.
5-inch (114-mm) Newtonian reflector with a focal length of 910 mm (f/8) that comes with a German equatorial mount and a gold-anodized aluminum tripod.
4 Newtonian reflector features a plate glass parabolic primary mirror in an eye-catching tube.
Extraordinary detail is visible on Jupiter's cloudtops in this tricolor CCD image obtained September 4, 1999, with a 10-inch f/8 Newtonian reflector from Di Sciullo's home in Coconut Creek, Florida.