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Summarizes key optical parameters like aperture, focal length, and performance metrics such as resolution and light grasp.
Explains how adding accessories allows the C90 to function as a telephoto, telescope, or spotting scope.
Lists the essential focal length, f/stop, and T/stop for telephoto photography with the C90.
Provides instructions on connecting 35mm SLR cameras using T-adapters and T-rings for photography.
Details the focusing process, range, and tips for achieving sharp images in various conditions.
Explains exposure control via shutter speed for the fixed-aperture C90, using meters or rules of thumb.
Guides on selecting objects, focusing, and viewing through the C90 as a spotting scope.
Guides the user through initial setup, including raising and positioning the tube using clamps.
Details how to use R.A. and Dec. clamps for initial positioning and viewing of celestial objects.
Step-by-step guide to polar alignment using Polaris (the North Star) for accurate celestial tracking.
Instructions on connecting and operating the electric drive system for automatic tracking of celestial objects.
Guidance on using setting circles and manual slow-motion controls to locate celestial objects.
Provides specific observing advice for the Moon and Planets, including recommended magnification levels.
Reiterates strict safety rules for solar observation, warning against improper filters or projection methods.
Guides on safely photographing the Sun using the solar filter and T-adapter, including exposure settings.
Instructions for photographing the Moon and planets, covering exposure and focusing methods.
Details using the tele-extender with oculars for extremely high magnification photography.
Provides detailed instructions on cleaning telescope optics, including approved methods and solutions.
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General