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Email page link to a friend| Rear cell filters |
| These filters consist of a #1A (pink) skylight filter in a metal cell that threads onto the rear cell of Celestron and Meade catadioptric telescopes. By sealing the Cassegrain focus at the rear of the telescope, they keep dust and airborne contaminants out of the telescope optical tubes during use and storage. They can be left in place permanently, but have a 14% light loss that can affect deep sky viewing. In astronomy, they visually increase contrast and decrease glare in lunar and planetary observing, although there will be a slight loss of resolution at high magnifications. Terrestrially, they are useful for visually and photographically reducing the effects of atmospheric haze in long distance observing. They reduce the blue cast in scenic photos to subjectively reduce the apparent aerial haze and reveal more detail in distant shots. |
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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 8 AM - 6 PM CST
Tuesday-Friday 8 AM - 8 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
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