Icing and dew

[Kevdan]

Hi All,

Had a good night out tonight but after about 9pm the scope started to get cold and eventualy had a icy glistening coat all over the tube, Is it ok to let this happen or should I be thinking about defrosting and keeping it warm to stop it. Also when bringing back into the house I just turn the scope so it faces down and let it warm up on its own and put it away in the morning when I get up for work. Is this ok or do I need to do something with the mirrors?

Thanks in advance,

Kev.

[Steep]

I'm no expert but what you are doing sounds about right. Put the caps on outside before bringing it in so that condensation isn't attracted to the cold glass.

/edit spelling

[Stevenebm]

I hate it when this happens.I do about the same as you.

[JamesF]

I thought the recommendation was to leave the caps off with the objective pointing downwards so any dew already present will run off rather than being trapped. The caps are then replaced once the scope is dry.

Not that there's much chance of condensation forming on a cold scope in our house

James

[Kevdan]

I knew it would happen sooer or later - Im actually doing something right, Thanks Guys

[brianb]

I knew it would happen sooer or later - Im actually doing something right

My scope gets condensation (dew or frost depending on the temp) on the tube just about every time it's used. It's a normal state, not an issue. So long as the optics are clear, it's OK.

Cover the scope before you bring it in - rubber shower caps are effective for mid sized scopes if you don't have "proper" end caps. Stire it with the tube level or pointing slightly downwards, not fully inverted which will tend to make the lenses/mirrors shift spoiling collimation. After a couple of hours (when all the condensation from the outside of the tube has evaporated) remove the end caps to allow any condesnation inside the tube (& especially on the optics) to evaporate.

[Penfold]

I was thinking exactly the same thing after icing up last night, did what brian suggested except leaving the cap on for a couple of hours. I normally leave if off the scope standing upright but thought this might cause pooling if any got onto the mirror. So phew everything seemed OK this morning.

[Rob]

Don't worry about ice and water dew. enjoy your obs session than as you have done bring into the house caps off all night, job done. dew water should not really leave any marks as its quite filtered (for want of a better word)

Rob