Condensation when bringing equipment back in house.

[GusTheSadGeek]

Hi, I am new here and new to the hobby.  Two weeks a go a bought a NEQ6 and 190MN and lots of extras via ebay. Still getting used to everything.

Last night I was getting used to polar alignment and guided tracking using just the small 80mm guide scope that came with the main scope.

At midnight when I brought the gear back into the house there was lots of condensation forming on the lenses. 

I left the scope until morning before putting the lens caps on so that the water had evaporated. Is this the correct thing to do ?  Especially when I start using the 190MN.

 

[RT65CB-SWL]

Hi @GusTheSadGeek and welcome to SGL.

“Yes!” You have done the right thing. Did you leave the caps off the eyepieces and other accessories too?

Also, when taken outside from a warm environment to cold environment, let it acclimatise [i.e cool down] before viewing, etc. It can take an hour or more. Not so long in warmer seasons though!

Edited March 4 by RT65CB-SWL

[M40]

Hello and welcome to the site.

Interesting telescope, let us know how you get on with it. With that meniscus lens on the front it will be very similar to the dew that lands on my skymax so first thing unless you already have one, is buy a dew shield. This will work well unless you point your telescope straight up. You could also look at a dew strap, fit it over the dew shield just in front of the meniscus. At end of play always leave the lens cap off until the telescope has dried out.

As your telescope is a used device, you will need to check it's collimation. Do this on a bright defocused star. Have a good read on this.

All the best

[Louis D]

If the air outside is super dry (dewpoint at freezing and below), you can cap your eyepieces and equipment to trap the dry air to avoid moist air from immediately hitting the cold optics and condensing on it when you bring it inside.  Once they warm up to room temperature after an hour or so, you can uncap them as a precaution.  If the eyepieces are stored in an airtight Pelican style case that is sealed with dry outside air before bringing it inside, you don't need to open it up.  The moist interior air won't get to the optics before they warm up.

If you have moist outside air, then what you are doing is the best.

[GusTheSadGeek]

Thanks for the replies.

I did leave all the caps off.

I have a heater due shield that I will use when I use the big scope.

It came with a laser collimater - which showed just a tiny offset - just before the battery went flat ! So I will have a ago at collimating when I get a new battery.

[doublevodka]

You are definitely doing the right thing, one thing I would add though is to point the scope downwards when you bring it in. This should minimize any airborne dust and debris collecting on any dew on the optics. On particularly bad nights you will find the whole scope covered in it, worth leaving the focuser/diagonal uncapped too, but pointing downwards if possible. You could even gently warm it with a hairdryer, although this is generally frowned upon by other members of your household late at night  

P.S. you will never stop dust getting on there completely so don't worry about it too much