Bringing scopes back inside

[hunterknox]

Hi All,

Simple question but I'm sure I'm not doing it right...

What's the proper procedure for avoiding dew when bringing scopes and eyepieces back inside?

[nightfisher]

here is what i do, bring them in and leave them without lens caps on for about half hour to make sure any dew has evaporated from the optics

[Freddie]

Same here.

[John]

I leave mine capped - this slows the warm up process and reduces the amount of dewing on the lenses. Bring a cold lens / mirror into the house uncapped and it dews almost instantly.

[calibos]

I finished an outreach event in Glendalough National Park a few years back. Orion XT12i OTA was covered in frost but the primary and secondary were fine right up till break down and pack up. I get home around 11 and decide to bring the scope straight out to the back garden to do some personal observing. Set the scope back up and can't see a blumming thing. Check I haven't left OTA dew cap on. No. Check I haven't left an EP cap on. No.

I look down the OTA only to see a layer of fern shapped jack frost a few millimetres thick on the primary!!

Aha! That'll be a supercooled primary and my moist breath in the car on the trip home then!!

If you can seal your OTA 100% to prevent warm humid household air from condensing on your cold primary at all in the first place, then one would seal it up outside before you bring the scope inside. If you can't make it airtight then bring it in and leave the caps off so that the condensate drys off as quick as possible

[Nexus 6]

Yea... which is the best method? I always cover the 925 as soon as its brought in, I will wipe of any condensation on the tube etc once done I cover it with a Green Witch telescope cover.

[Luke]

ditto here, half an hour

here is what i do, bring them in and leave them without lens caps on for about half hour to make sure any dew has evaporated from the optics

[vince 66]

I always cap my scopes outside and then carry them into the house. I always check the next day to make sure the opics have dryed out ok so far no prblems.

[Zul]

I bring all the stuff capped but after 10 mins i open the caps and leave them uncapped.

[kirkster501]

I was wondering this exact same question. I want a method that I can cap it up, lock it up in the [cold] garage and forget it until the following morning. I can't be sitting around waiting for complete "dry out" at midnight when I need to be up at 05:30.....

I have a large Stanley storage box that I take with me to the back yard ready for break down. When the - perhaps dew covered - scope gets taken down, I take it that Ishould leave the box uncovered and let it "air out" a bit (albeit with it capped) ?

[Chris H]

I was wondering this exact same question. I want a method that I can cap it up, lock it up in the [cold] garage and forget it until the following morning. I can't be sitting around waiting for complete "dry out" at midnight when I need to be up at 05:30.....

I have a large Stanley storage box that I take with me to the back yard ready for break down. When the - perhaps dew covered - scope gets taken down, I take it that Ishould leave the box uncovered and let it "air out" a bit (albeit with it capped) ?

My Dob lives in an unheated shed, when I have finished observing it goes in the shed uncapped but at an angle so nothing can fall onto the primary I have a dehumidifier that I then switch on that runs for three hours on a timer. In the morning I pop in the scope is always dried out and I put the caps back on.

[Demonperformer]

For the first time this morning, I found the corrector plate had dewed up by the end of the session (new scope requiring new dewshield which is not fully lined yet, so obviously not fully functional). Brought it in, removed cap, scope angled down, dew all evaporated within 30mins. Job done.

[kenmyers]

I never worry. If my scope dews/mists up I count that as my session over.

I always pack up outside, put on the cap, pack up eyepieces and carry indoors.

I keep my telescopes in my garage and it is quite a cold concrete room.

I think this helps.

[todd8137]

well theres no simple answer as you may have found out ,if brought into a heated house your going to get dew ,heres what i do ,bring my scopes in ,wipe the out side of the tubesi do not cap the tubes at all,i then usally put some silca gel bags in the reflector and cover with a old quilt cover so the end of the tube is loosely covered i keep them in my pantry which is 4feet wide and 12 feet long the refractor gets a good wipe down i angle both tubes at 45% pointing downwards,shut the door and goto bed ,theres no heating in the pantry and is cool all the time ,with eps all i do is check them over and put a towel on the table in my pantry lay them on it wipe any heavy due of i Do not clean the glass on the eps and then lay a old piece of table cloth over the top

to avoid dew get a due shield or make one out of a cheapo black camping matt of the net some were a friend got one the other day for 6 quid delivered he made a dew sheild and a light shroud so cheap all round dew heaters are not cheap and may be a idea to check the diy section to see what people have made on that front, the main prob with dew on glass is things sticking to them once brought inside thats why i hang a sheet over them to stop dust getting on a damp mirror

clear skies

[Demonperformer]

may be a idea to check the diy section to see what people have made on that front

I know someone who had success with this: Home made dew heater

[moriniboy]

I have been considering leaving the ED120 dew shield extended, putting cling film over the end then using the end cap to hold it all in place, only then would I bring it back inside.

I'm thinking that if the moist air can't get to the lens then no dew can form.

Suppose I will have to do it both ends.

Can anyone spot any obvious flaw with the above?

[kev]

The only problem with capping the top when you bring it in, whoch is what I used to do, is that these days the damp still gets in via the fan under the mirror.

Ho hum

[Charon]

I always cap mine outside too, never have any problems.

[SaraG]

Mirror's wont dew up on a sealed Maksutov right?

[moriniboy]

Tried the cling film and dust cap (see above post) for the past 2 nights and condensation still formed on the lens when I brought it inside. However the amount of condensation that formed was less than I usually get and isolated to the centre 1.5".

I'm going to carry on with this method because it reduces the amount of condensation and it allows me to remove the dust cap to check how things are progressing.

[cs1cjc]

I simply accept the dew and leave things out to dry until the morning, with the fan on in the case of my 14". I worry less about the dew and more about putting equipment away while it is still damp.

[moriniboy]

Ive just used a 2" to 1.25" adapter to make my own drying aid for the inside of my refractor (paranoid about mould growth)

The silica beads I used are colour change ones and 2 to 4mm in diameter, I drilled 1mm holes in the base and used some foam as a further filter to make sure nothing untoward gets into the tube.

Cost £5.50 for 500g of beads and everything else free.

Well chuffed.