Before cleaning the corrector plate, go back and re-read the last few paragraphs of Chapter 2. Then sit down and read a book or make a hot fudge sundae. Maybe the desire to clean the corrector plate will go away by the time you're finished. Cleaning has more potential for permanent damage to the telescope than any other operation. In the nearly 20 years that I have owned a 20-cm S–C I have had to clean the corrector only once and that was when I allowed heavy dew to form on the telescope. The dew contained industrial chemicals from a nearby city which created a gray-green film. I had also been warned that some of the chemicals could etch the glass. It would have been smarter of me to prevent the dew forming in the first place.

First blow off the dust using ‘canned air’ since you don't want any of these loose particles adhering to the glass when you wet it. Next, fill a spray bottle of the type used to clean windows with pure distilled water. With the corrector plate vertical (tube horizontal), spray the glass all over. The object here is to allow the water to dissolve all it can and carry off the dirt. Do not rub the glass since this can grind small dust particles into the glass and produce permanent scratches. Use plenty of water to allow it to flush away the grime.