Return to the Cloudy Nights Telescope Reviews home page


Telescope Specific Forums >> Celestron NexStar

Pages: 1
Illsonmedia
super member


Reged: 11/25/11

Loc: Washington, DC
Proper care of sgt-c6?? new
      #5533788 - 11/22/12 11:29 AM

Last night I brought my sgt c6 outside. it was about 35 degrees. I brought the scope out and let it sit for about 2 hours. I left all the caps/covers on.

I then spent about 2 hours viewing. Towards the end of my viewing, everything was covered in condensation. The lens of my telescope was wet. Are you supposed to wipe that off, or is it a big no-no to touch the front, main lens of the scope?

When I bring the scope back inside, should I put the covers back on immediately, or let it adjust to room temperature first?

It was just weird bringing a wet telescope back into my house and not knowing what to do with it. Thanks.


Post Extras: Print Post   Remind Me!   Notify Moderator  
Maverick199
Postmaster
*****

Reged: 02/27/11

Loc: India
Re: Proper care of sgt-c6?? new [Re: Illsonmedia]
      #5533852 - 11/22/12 12:18 PM

You should keep the scope pointed DOWNWARDS till the condensation completely evaporates. DO NOT WIPE. Put on the covers only after evaporation.

Post Extras: Print Post   Remind Me!   Notify Moderator  
trw
member


Reged: 07/28/09

Re: Proper care of sgt-c6?? new [Re: Illsonmedia]
      #5533857 - 11/22/12 12:20 PM

Once back inside, I usually just let everything dry out before recapping, on the principle that wiping at optical surfaces should be kept to a bare minimum. Condensate this time of year is pretty clean and should not leave much if any residue on the glass. During pollen season, though, condensate can trap and leave a visible layer of pollen on surfaces which may need to be very gently removed--it is very abrasive.

Post Extras: Print Post   Remind Me!   Notify Moderator  
mclewis1
Thread Killer
*****

Reged: 02/25/06

Loc: New Brunswick, Canada
Re: Proper care of sgt-c6?? new [Re: trw]
      #5533904 - 11/22/12 12:46 PM

And work towards not getting heavy condensation on the corrector in the first place ...

Use a good flexible dew shield. If a commercial model isn't working out consider making your own and size it longer than commercial unit (~11" in the case of the C6), I'd suggest 18" or so.

Use a heated dew strip and controller to very slightly raise the temp of the corrector to help prevent the dew from forming.

Another option some folks use is a 12v "blow drier" to blow air over the corrector. You can also use a "real" hair drier but make sure not to use any substantial heat. If you use a real hair drier leave it on just blow or a very low setting and move it well back from the corrector when using it. You don't want to heat any surfaces at all ... just move the air around to help evaporate any dew/condensation that's formed.

If you absolutely cannot get the optics completely dry before storing them then use desiccant to absorb any moisture without having to touch the optics.

Using these methods the corrector will stay dry (or close to it so the evaporation back in the house will be quick). Remember though that bringing a cold scope back into a nice warm house can also cause serious condensation to form on the surfaces. It is usually best to move the scope in two stages ...

1) From the back yard observing area to someplace covered but open to the air. Leave the corrector uncovered (and take the dew shield off) and pointed slightly downwards. This will allow any dew that's formed to evaporate.

2) Then into the house. Here you do want to cap your scope before you move it. You want to trap the drier cold air against the corrector. When you bring a scope like this into the house there is less likelihood of condensation forming because of the warm moist air in the house.

And remember that a little dust on your optics is much less of an issue than water spots and the like. It's not the end of the world to leave your optics un capped and pointed downwards.


So to recap ...

1) prevent the dew from forming in the first place wherever possible
2) don't cap wet optics
3) use drier air to insulate against the moist air in your house when your scope is still cold


Post Extras: Print Post   Remind Me!   Notify Moderator  
Illsonmedia
super member


Reged: 11/25/11

Loc: Washington, DC
Re: Proper care of sgt-c6?? new [Re: mclewis1]
      #5534209 - 11/22/12 04:57 PM

This is great--sounds like maybe I can use the drier method tonight. I have to confess, I did wipe the front lens (sounds like it is called a corrector?).

I wiped very gently, with only enough pressure for the cloth to absorb the water. Well...I now do have some streaking on the corrector.

Any recommendation on how to deal with this? Or should I Just accept it, and probably stop doing more harm than good?

Thanks for all the detailed responses by the way.


Post Extras: Print Post   Remind Me!   Notify Moderator  
mclewis1
Thread Killer
*****

Reged: 02/25/06

Loc: New Brunswick, Canada
Re: Proper care of sgt-c6?? [Re: Illsonmedia]
      #5534302 - 11/22/12 06:20 PM

Don't worry about minor streaks on the corrector, they won't affect the views through the scope. You can take care of them at some point in the future when you really need to clean the corrector.

Gently wiping a few times to remove dew build up isn't going to hurt anything, the problem comes if you do it continuously night after night. The more often you clean/dry the corrector the more likely you are to drag bits of grit and scratch it. Like minor streaks, minor scratches aren't going to be a problem, you just don't want a bunch of them building up.

When you do need to clean or dry the corrector use single use lintless cloths or cotton balls. (basic rule: don't reuse anything that comes into contact with the corrector)


Post Extras: Print Post   Remind Me!   Notify Moderator  
Pages: 1


Extra information
5 registered and 14 anonymous users are browsing this forum.

Moderator:  Brian Risley, panhard, Mitchell Duke, mayidunk 

Print Thread

Forum Permissions
      You cannot start new topics
      You cannot reply to topics
      HTML is disabled
      UBBCode is enabled


Thread views: 381

Jump to

CN Forums Home




Cloudy Nights Sponsor: Astronomics