Ice inside scope - what to do now?

[wulfrunian]

I'm abandoning things tonight - the sky is just getting hazier, and my finder's lens is frozen over so I can't find anything anyway. But there's also ice inside the top of the tube, over the spider vanes and on the inside of the tube. If I just pack away now, with the tube vertical as usual, this will melt and drip onto the primary, won't it - should I try and dry this somehow indoors first?

And what do other people do to stop their finders freezing up??

[Rob]

You can buy a heater strap?.. see FLO

[Doc]

I use a dew controller with a band for the telrad and a homemade wraparound stalk heater for the secondary. These never dew or freeze up now but the outside always does.

[wulfrunian]

So I'd need some sort of power supply set up to stop it happening in future then.

Am I right that I need to warm the scope up indoors horizontally now before packing away, so the ice doesn't melt onto the primary?

[brianb]

If I just pack away now, with the tube vertical as usual, this will melt and drip onto the primary, won't it

Try to store with the tube horizontal, so that drips / foreign bodies falling or crawling into the tube don't hit the optical surfaces.

Evaporate condensation - whether frozen or liquid - before fitting the caps. A low power hair dryer is useful.

[wulfrunian]

Try to store with the tube horizontal, so that drips / foreign bodies falling or crawling into the tube don't hit the optical surfaces.

Evaporate condensation - whether frozen or liquid - before fitting the caps. A low power hair dryer is useful.

No storage room at the moment for it to be horizontal! I'll bring it in and get the hair dryer on it before i put it away. Then I'll spend more cash on dew strips, a controller and a battery pack!

Thanks for the quick replies

[Theninjagecko]

For me my homemade Dew sheild stops any ice forming inside there. Cardboard dewsheild waterproofed with sticky tape.

Get the scope in, dry it off and keep it in a horizontal position to dry over night. I left my 300p dob vertical with bad dew and it dripped all over my primary

[Theninjagecko]

In regards to finder, i have another homemade dewshield on that, and when not in use i put the cap on the bit you look through.

[Beulah]

Ooops.

Unfortunately I don't have room to store my scopes horizonally...Dobs are big brutes!!

My mirrors are due a clean anyway..

[wulfrunian]

Ok, everything's inside now and dried off with a hairdyer. I can leave the dob in the house overnight horizontal to make sure. Then I'll investigate dew and ice prevention - not known it this bad before.

Do you just cut cardboard to shape and then cover it with sellotape? How do you secure it to the scope and finder? Do you have to keep renewing it?

[Theninjagecko]

Ok, everything's inside now and dried off with a hairdyer. I can leave the dob in the house overnight horizontal to make sure. Then I'll investigate dew and ice prevention - not known it this bad before.

Do you just cut cardboard to shape and then cover it with sellotape? How do you secure it to the scope and finder? Do you have to keep renewing it?

Cut long piece out and measure it all nice. It stays on because its a snug fit. Squeeeze it down over the ends of the scope and finder. The tape took 2 roles but its covered now so its waterproof, plus no paper cardy bits can come off into the scope.

This is the sheilds first light, after this session i added all the tape. Wanted to make sure it worked. Since this shot i made another one for the 250. Works a treat, scope has been out since about 5 covered in ice but the mirrors are still fresh icey free

http://stargazerslounge.com/observing-reports/92217-30-11-09-cold-wow.html

[wulfrunian]

That looks like a seriously good idea - that's now on my list of things to do during this week off

So far since buying the scope I've been thwarted by clouds, flu, work, and now ice. But I did enjoy that half hour tonight viewing the Pleides before watching the match - I should have just stayed out and got some more viewing in before it got too icy, the game was dire anyway!

[Theninjagecko]

Took these just 22:35. But she will last all night.

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