Did you ever try to break your scope before? I doubt you dare. I maybe the first LX90AT user with the cracked corrector plate.
Here the story begins.
If anyone remembered my previous post about disassembling the LX90AT, you should know why I removed the corrector plate. Yes, I dropped a toothpick into the OTA from the visual back. All of the nightmare started from here. I bought a Purosol Optical (PO below) and their microfiber cloth as I planned to clean the corrector plate. In the end, I cleaned the primary mirror as well because the PO claimed that the solution was enzyme based and would not hurt the coating. That’s true, just that the microfiber cloth left quite a lot of fiber behind.
This time, after the Kluang 100 Hours Starparty, I decided to clean my corrector plate which was stained by fingerprints. I knew I had to blow off the dust before I apply the Purosol Optical to prevent the particles from marring the coating and the glass. I used an air compressor… =.= I only realised that the air compressor was not well filtered after I found out there’re blue stains on the corrector plate and the primary mirror. I suspect that was oily substances. I managed to clean the corrector plate very well with the microfiber cloth and the PO solution. That’s the same case for the primary mirror.
Now’s the climax. After I put the corrector plate back into the optical tube assembly (OTA) housing, I turned to my desk to get the screws. Voila! The OTA falls towards the ground and the corrector plate falls off to the ground accompanying with an ear piercing sound. I couldn’t accept what was happened in front of me. Luckily, the secondary mirror survives.
The culprit was that I didn’t lock down the DEC axis. Therefore, the gravity balanced the scope without much frictional force.
In conclusion, I shall be more careful while handling expensive optics and not do anything which requires full attention during the unearthly hour. Well, I admit that my perfectionism and curiousity led to this event.
Did I say that the corrector plate and the primary mirror do not need any cleaning unless they are really really very dirty and seriously degrade the optical performance? This is my advice to the newbies. Keep away from the lenses and the mirrors and only clean it when it’s desperately demanded. Fire the flashlight on the primary mirror will reveal some substance that will not ever affect your scope performance. Don’t take that eyesore serious. The same goes to the primary mirror. Last but not least, DON’T use air compressor to blow off the dust. Do only use canned air for scientific instruments and optics.
