Avoiding condensation on an Achro lens.

[crepitis]

Last weekend was the first chance Ive had to spend some time trying out my Tal 100RS refractor.

It was very cold , and there was a heavy ground frost. During observing I didnt notice any problem with the objective dewing up and the dew shield seemed to be doing its job.

When I finished for the night, around 2 AM I replaced the end cap on the dew shield and brought the scope indoors.

The next morning I noticed condensation on the outside surface of the objective when I removed the end cap.

For future reference, should I bring the scope indoors with the dust cap left off, and remove the dew shield, or is there some other combination of doing things that doesnt result in condensation on the lens , I would hate to damage the optics in some way.

Can any of you more experienced refractor owners advise me please.

[jgs001]

I normally bring mine in with the cap on, more to protect the lens cell in transit, then point the scopes objective downwards and leave the caps off till the following morning to dry out. Seems to work ok...

[crepitis]

I dont usually store it mounted so pointing it downwards would be difficuilt, if its left in a warm room overnight I take it that it would be best to leave the cap off ?

Another thread ,elsewhere on the forum ,where it seems that moisture has got trapped between the elements in someones Achro refractor just got me a bit concerned that I was doing the wrong thing when bringing it in for the night.

[SpookyKatt]

I just bring the scope in and lay it flat with the end cap

off and just leave it til morning.

Kathleen

[GazOC]

Same here but slightly inclined just in case any moisture finds its way inbetween the elements (probably not needed).

[crepitis]

Thanks guys for your help , I guess the problem was leaving the cap on overnight, I'll make sure I leave it off next time.