If your Schmidt has been extensively handled or subjected to wide variations in temperature and humidity in an observatory, or is experiencing focus problems, you might consider removing the rear cover of the camera for a mirror inspection before you attempt further servicing or focusing. An inspection with the back cover off will reveal whether the mirror needs to be completely removed for realuminizing. ound that my own camera's mirror had not aged well. The aluminizing was so thin that I could see through it and the coating was heavily pin holed. Shining a light in from the rear of the camera and viewing into the tube from the corrector plate end revealed a scene that looked like a tin roof punctured by blasts of buckshot.
|Removing the camera's back cover and shining a light in from the rear will reveal the condition of the mirror. In this case, the author's camera shows the results of 25 years exposure to everything from high humidity to ants that crawled into the camera durring an extended cloudy period, then died on the mirror.|
|Removing the rearmost three screws from the tube allows the back cover to be released.|
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