|
|
| An optical defect in which star images are elongated into ovals which change from a radial orientation (pointing towards the center of the field) to a tangential one (at right angles to the center) as the observer moves the telescope focuser from one side of the best focus to the other. Should not be confused with the star images of an out-of-collimation telescope, which may also be oval but which will not change orientation as the observer passes through best focus. |
Home | How to pick a telescope | Telescopes | Accessories | New Products | Used & Demo / Special Sales | Binoculars & Spotting Scopes |

Link Support
Terms of Sale | PRIVACY POLICY 7/1/2004 | Fine Print
Toll-Free Telephone Astronomics: 800-422-7876; Christophers, Ltd.: 800-356-6603 Alternate Telephone: 405-364-0858 24 Hour Fax Line: 405-447-3337
Telephone Hours: Monday-Friday 8 AM - 9 PM CST Saturday Noon - 5 PM CST
Store Hours: Monday-Friday 9 AM - 5 PM CST Saturday Noon - 5 PM CST
Astronomics / Christophers, Ltd. 680 S.W. 24th Ave. Norman, OK, 73069
© 2008 by Ad-Libs Advertising, Inc. All rights reserved
|
|