Cleaning my 8" Celestron

[Moonshed]

I have owned my Celestron for 25 years now and never cleaned the mirrors, the reason being I have no idea how to get to them. I am too nervous to just start unscrewing because I have no idea what is happening and don't want to do any damage. Any advice would be appreciated.

Keith

[ronin]

Likely little point in cleaning the mirrors unless you can see a good build up of dust and whatever. The mirror is reasonably well protected - however dust and moisture will have got in but likely in small amounts. Difficult when you talk of 25 years. Even a very low ingress of dust builds up over that period, and unfortunately dust and moisture tend to create something tha tcan get well adhered.

One option is to look up SCTelescopes and enquire about having it cleaned and checked over. SC (Steve ?) does a good job from reports and at a good price. I think )only think) he is in Kent (Well somewhere down South). So it may be better to enquire and take the scope down if you decide on that option. It presumes that he will do the scope while you wait. Traffic will be bad however.

If you have a link to it I think that SCTelescopes advertises on the ABSUK front page.

[michael.h.f.wilkinson]

My C8 is 20 years old, and I have not seen any significant build up of dust on the mirror. I have only ever cleaned the corrector plate. If I ever feel the mirror needs a clean, I would probably try to find a professional to do it for me (and perhaps even recoat the mirrors).

[SteveBz]

I don't know about such mature scopes, but my modern Celestron scopes come apart quite easily. There are screws at the base of the tube at 120 degree intervals and the whole cell slips off.  I find mine slip off and on again with only minimal recollimation.

You can find plenty of youtube videos about cleaning the primary lense with cotton wool swabs. I've never done a full cleanse but I have done the occasional quick clean job just to get the occasional bit of pollen or whatever.

Most of the screws are self-tapping and easy to refit. Only the nut and bolt types are hard to get together because there is nothing to hold the nut.

Good luck,

Steve

Edited August 25, 2016 by SteveBz

[SteveBz]

Like here

 

 

[michael.h.f.wilkinson]

25 minutes ago, SteveBz said:

Like here

 

 

Your C8N is a Newtonian (hence the 'N'), a very different beast from the C8, which is an SCT. The C8N is open at the front, so much more dust accumulates. The C8  has a closed tube (the Schmidt corrector plate is mounted up front, keeping almost all dust out), so the mirrors are not very accessible

[Moonshed]

Thanks for all your advice. I think the one thing that has come across is to get it done professionally, which confirms my feelings on the matter, I don't think it is something I would like to tackle myself. If on the other hand I was told it was a simple matter of unscrewing a couple of bolts I would have given it a go, but now I think not. The tube has NEVER been left open, either plugged with an EP or a cap so perhaps it's best just to leave well alone. I thought maybe it was just me and everyone else cleaned their mirrors. Guess not. Thanks again.

Keith

[SteveBz]

Ok it's true.

Ignore my comments, sorry.

[michael.h.f.wilkinson]

The key question I always say is not whether there is some dust in the optics, but whether the images you are getting are good. If so, don't touch the optics is my motto (or maybe that is just an excuse for laziness ).

[Moonshed]

5 minutes ago, SteveBz said:

Ok it's true.

Ignore my comments, sorry.

No problem, I realised you were talking about a Newtonian, I had one previously and it was relatively easy to clean. I have decided not to clean mine, leave well alone.

[Peter Drew]

The Primary mirrors on Celestron and Meade SCT's are removed from the front of the OTA which requires that the corrector plate is first removed. If you try to remove the rear cell  then the nuts fall off inside, you then have to remove the optics as before to reattach them!  If at any time you decide to remove the optics, get back to the forum, or PM me, for further advice.

[Wurthman20]

I’m also needing to  get mine professionally cleaned and collimated

im in Charleston SC any ideas?

regards,

phillip