Celestron C90 Instruction Manual
  1. Manuals
  2. Brands
  3. Celestron Manuals
  4. Telescope
  5. C90
  6. Instruction manual

Celestron C90 Instruction Manual

Hide thumbs Also See for C90:
Table of Contents

Advertisement

Quick Links

See also: Operating Manual , User Manual

Advertisement

Table of Contents
loading
Need help?

Need help?

Do you have a question about the C90 and is the answer not in the manual?

Questions and answers

Subscribe to Our Youtube Channel

Related Manuals for Celestron C90

Summary of Contents for Celestron C90

  • Page 2: How To Use This Manual

    How to Use this Manual This manual explains the proper use of your Celestron spotting scope —from initial set up to on- going use. This manual is broken down into several sections. The first covers attaching your spotting scope to a stable platform, like a photographic tripod, so that the standard accessories can be attached.

  • Page 3: Getting Started

    WARNING Never adjust the three screws located in the rear cell of your C90 as these are solely for manufacturing adjustments. Any adjustments of these screws will automatically void your warranty. Please contact Celestron if you feel your C90 is out of collimation.
  • Page 4 THE C90 SPOTTING SCOPE This section covers the correct set up and operating procedures for your Celestron C90 spotting scope and includes information on visual and photographic observations. The C90 spotting scope uses a combination of mirrors and lenses to produce an image.

  • Page 5: Removing The Lens Cover

    1. Remove the protective cover from the rear cell of the C90, the 45º Erect Image Diagonal, and the eyepiece. 2. Loosen the thumbscrew on the rear cell of the C90 so that the opening (i.e., inner diameter) is unobstructed.
  • Page 6 Focusing To focus, turn the focus ring on the C90 tube until the image is sharp. On the rubber covered C90, turn the front portion of the lens to focus. For objects closer than the one you are currently observing, turn the focusing ring clockwise and for objects further away, turn counterclockwise.

  • Page 7: Aligning The Finderscope

    Tighten the thumbscrew on the 45° Erect Image Diagonal to hold the eyepiece in place With the new eyepiece in place you will need to refocus your C90 (unless the eyepieces have the same focus point, something known as being parfocal). Once again, turn the focusing ring until the image is sharp.
  • Page 8 C90. The T-Adapter, then threads over the filter to hold it in place. Attaching a Video Camera The C90 can be adapted to a video or Super 8 movie camera by using the optional T-C 16mm Adapter (#93636) and the C90 T-Adapter (#93635-A). To attach a video camera to the C90: Remove all accessories from the C90.

  • Page 9: Carrying Case

    Storing Your C90 To minimize the need to clean your C90, replace all lens covers after use. The spotting scope can be left on a tripod for display purposes or returned to its shipping carton. Since the rear cell of your C90 spotting scope is not sealed, the eyepiece or protective cover MUST be placed over the opening in the rear cell when not in use.

  • Page 10: Calculating Magnification (Power)

    C90, the maximum useful magnification is 210 power. This is derived from multiplying 60 times 3.5. Although this is the maximum useful magnification, most observing is done in the range of 20 to 35 power for every inch of aperture which for the C90 is 70 to 105. Field of View Determining the field of view is important if you want to get an idea of the size of the object you are observing.

  • Page 11: Reducing Vibration

    PHOTOGRAPHY HINTS Metering Celestron spotting scopes have fixed apertures and, as a result, fixed f/ratios. To properly expose your subjects photographically, you need to set your shutter speed accordingly. Most 35mm SLR cameras offer through-the-lens metering which lets you know if your picture is under or overexposed. Adjustments for proper exposures are made by changing the shutter speed.

  • Page 12: Observing The Sun

    A spotting scope is nothing more than a telescope that produces correctly oriented images. That is why all Celestron spotting scopes are so well-suited for looking around the Earth. But this in no way limits the spotting scope to terrestrial use. On the contrary, the C90 spotting scopes work well as astronomical telescopes for observing the sky.

  • Page 13: Observing Deep Sky Objects

    Because your spotting scope is not set up for serious astronomical observing, you will need to know where to look in the sky for these objects. The Celestron Sky Maps (#93722) will help you locate the brightest deep sky objects.

  • Page 14: Care And Cleaning Of The Optics

    Or liquid dish soap diluted with water (a couple of drops per one quart of water) can be used. Internal adjustments and cleaning should be done only by the Celestron repair department. If your spotting scope is in need of internal cleaning, please contact the factory for service.
  • Page 15 As a condition to the obligation of CI to repair or replace such product, the product must be returned to CI together with proof-of-purchase satisfactory to CI. The Proper Return Authorization Number must be obtained from CI in advance of return. Call Celestron at (310) 328-9560 to receive the number to be displayed on the outside of your shipping container.
  • Page 16 2835 Columbia Street Torrance, CA 90503 (310)328-9560 (310) 212-5835 (FAX) Web site: http:\\www.celestron.com Copyright 1997 Celestron International All rights reserved. Products or instructions may change without notice or obligation. Item #93987-95 07-98...

Table of Contents

Save PDF