View Full Version : C-8 Corrector Plate

2004-May-09, 02:42 AM
Last night while waiting for darkness and Q4 NEAT to come out, I inspected the corrector plate with a jewelers magnifier The scope is over 20 years old, and while the images it produces are still pretty good, I was surprised at how much dirt and grit had accumulated on the inside over the years. Plus there is a thin fog on the inside of the plate.

Does anyone have any advice on how to clean the inside of the plate? On my old refractor, I would just unscrew the objective and clean it. I'm a little reluctant to do that on a Schmidt-Cass. Thanks

Kaptain K
2004-May-09, 03:26 AM
From the Celestron FAQ page:

Q: How can I clean the corrector plate on my Schmidt-Cassegrain telescope?

A: The outside of the corrector plate can be cleaned using a solution of 60% distilled water and 40% isopropyl alcohol with one drop of clear liquid dish soap per quart of solution. The solution is applied to a soft tissue or cotton ball and is carefully rubbed onto the corrector plate using radial strokes from the secondary mirror housing outward. We do not recommend removing the corrector plate. The corrector plate is optically matched to the mirrors in alignment and in rotation. If the inside of the corrector plate or mirrors becomes dirty, call Celestron and arrange to send your telescope in for a thorough cleaning. Celestron offers complete cleaning and collimating services. Contact the Technical Service Department at (310) 328-9560.