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Terry Wood

Jupiter (clearer) Nov 5th 2023 w/Mewlon 180c

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6 inch f8 scopes

Started by [email protected], 05/10/2003 01:05PM
Posted 05/10/2003 01:05PM Opening Post
With all the current interest in 6 inch achromats, I would like to put in a plug for the venerable 6 inch f8 Newtonian reflector: The same mount that carries the achromat will carry the reflector, but because the scope does not ride as high on the tripod or pier the mount will be more stable. A third advantage: virtually identical performance without the chromatic aberration at lower cost; no parracors required. A fourth advantage: mechanical simplicity, easy collimation. A fifth advantage: because of the long focal ratio, small secondary mirrors, reasonably accurately figured mirrors and forgiving collimation lead to stunning views through the scope. That said, however, a 90 f/5 achromat mounted to rings makes a killer finderscope and complimentary wide field scope, and things really get good with a minus violet filter in the optical train of the short tube scope.
Posted 05/10/2003 01:12PM #1
Ted,

In high school and college, I owned a 6" f8 Criterion Dynamax that I stupidly sold when I bought a C8. This was a nice scope that I didn't really make good use of, because of my limited knowledge at the time. I agree that 6" f8 scopes are top-notch.

Gary