eyepiece misting

[Kevdan]

Hi All,

Having a good night but now the temps have dropped my eyepieces keep misting up, how do i stop this.

Kev

[flateckers]

My brothers a scuba diver, his mask had a tendacy to mist over. He would use shaving foam on a cloth then dry it with another. I use it in bathroom mirror works a treat. Not sure about optics though.

[sooren]

A dew heater round the diagonal

Regards

Paul

[Kevdan]

how do you do that then?

[WayBig]

I always cap mine when not in use, and the only time they've ever misted over is when i've accidentally breathed on them.

My finder scope always mists over though, I never think to cap that.

[Doug]

Hi Kev

I use a small hair dryer runs of a 12v battery I use a power tank also runs of a car lighter socket there only £10.49 see web site

Clear skies

VirtualVillage.co.uk

[LukeSkywatcher]

Keep them in a coat pocket or in a case until you use them. If they mist up while in use then a quick rub with an opticians cloth (non lint) is enough to get them going again.

[sixela]

The most important thing to do is to avoid exposing the outer lenses to the night sky (that includes not leaving them in the focuser when you are not behind them). That's because dew forms when eyepieces cool under the ambient temperature due to radiative losses to the night sky.

Those eyepiece racks conveniently installed by mass Market producers are, frankly, not to be used unless you always re-cap the eyepieces.