OTA storage - 8" Newt

[Leebert]

Hi all,

Quick storage question please now the earlier dark nights are coming...

I'm looking to store an OTA in the garage so it is closer to ambient temp. The garage is dry but not completely sealed to the outside (ie. it's draughty) - is this okay?

Secondly, is it okay to store a 8" newt horizontally or is it preferable to store them mirror down?

Many thanks,

Lee

[hemihaggis]

i dont see a problem with a little draught , its the moisture you need to watch out for , and as for vertical or horizontal ... well i would store it where ever practical !

[dweller25]

I stored my 6" Dob horizontally in the garage for years BUT I hung it from the roof - the biggest enemy is the damp floor in a garage.

[IvanT]

What about leaving it permanently setup in the observatory? Mine, a custom built roll back shed is going in tomorrow (weather permitting). From last year it's been stored raised of the floor with primary slightly raise in the garage and it's been fine but I'm concerned that left permanently setup with just the scope front cover on might damage it over time?

Sent from my iPhone using Tapatalk

[umadog]

Depending on your garage, you may want to keep dew mind. If in the mornings the surrounding air warms substantially faster than the mirror then the mirror will get dew forming it. If this happens regularly then you will end up with a destroyed coating. This has happened to me. You may never see this dew as it evaporates once the mirror has warmed. If this is a concern, you will want a little heater on a timer to keep the mirror from dewing.

[Leebert]

Thanks for the replies.

For some reason I got it into my head that it's not good to store the OTA horizontally

I wasn't thinking of permanent storage. Just popping the OTA in the garage a day or so before a good forecast. It would normally be kept in the house.

Thanks for the heads up on dew ruining the mirror coating. I have an old beer heater from my brewing days I could use for that. It's just a low wattage light in a metal biscuit tin (10 watts I think).

That only got just warm but I guess would keep the very local area around the heater warm enough to prevent dew from forming but not too hot so that I had to wait for the mirror to cool down if I wanted to use it maybe?

[Pete Presland]

i think it will be fine,in the garage.

[Moonshane]

given your comments I'd just put it in the garage in the morning before work and then it will be more than well cooled when you get home. I store mine in the house too.

[sungazer]

Hello Leebert,I have always kept my scopes in the garage, either on the wall on tube cradles, or standing up. The most important thing in my opinion is to keep dust of the mirrors or lenses as this can contain acidic compounds which can effect the surfaces.Just my findings of 50 years of telescope use.John.

[Leebert]

Interesting that you should mention dust as that is another question that I have.... How much is too much? An OTA that I am considering has some dust on the primary mirror. It's more specks than a layer if that makes sense but there is some there nevertheless. What is the best way to remove / clean it or is it best just left?

Thanks.

[Angelika]

Everyone, so far, has mentioned storing a scope indoors. Am I risking alot of problems by leaving my telescope on my deck through the fall and winter? I have a cloak cover on my telescope all the time, which advertised that:

- Scope Cloak protects your telescope when it's idle, shielding it from the

elements - dirt, moisture, and sunlight

- In the daytime it will keep your scope cooler so it will reach thermal equilibrium

faster once night falls

- It's made from reflective, tear-resistant fabric with a waterproof lining. A

locking drawstring provides a snug fit

Should I be storing it indoors in the winter ?? It does get mighty cold here.

Thank you for your advice.

[James]

Mine stuff sits either in my shed or garage. When it's left outside I do use a decent scope cover and my mount and pier are permanently outside and covered. But... It's worth leaving the kit out for a night or two then checking under the cover as it's possible you'll still get moisture/dew etc collecting under the cover...

James

[umadog]

Your 8" should reach thermal equilibrium pretty quickly if you add a fan. You can monitor that by in-focusing a lot on a bright star. You can actually see the convection cells moving slowly across the mirror at higher powers. Once it's settled down, these go away.

My main issue with scopes in winter is that bringing them back into a warm room causes condensation to form on the primary. This shortens the lifetime of the coatings and makes dust stick to them in an annoying way.

In summer I keep my scope in the house. In winter I keep it in the basement, which is unheated. I've found that bringing the scope into the basement from outside doesn't lead to condensation. I don't keep it down there in the summer because it's rather damp.

I have heard of people keeping their scopes outside under a suitable tarp. Certainly at star parties this is what people do. In fact, at the last star party I went to there were dozens outside weathering a hurricane. Again, as a long-term storage solution my main concern would be the issue of dew in the mornings.

I don't know the mechanism by which the dew damages the coating. One explanation I've heard is that dew, being pure water, has no salts in it to buffer pH changes. Acidic pollutants readily dissolve into dew and can rapidly change the pH and so eat away at the coating. I was told that one should immediately wash away dew with distilled water to avoid this. Now that doesn't make sense to me since distilled water also has no salts in it. My hunch is that the dew is disolving solid particles (dust, pollen, etc) deposited on the mirror, not atmospheric pollutants. Stuff leaching out of those solid particles may be damaging the coating. Washing regularly with distilled water will therefore flush away those particles and make the dew less damaging.

[Angelika]

Forgive me for being so dense, if the scope is left outside there is a possibility of dew, if the scope is taken inside every night there is the possibility of some condensation... what is the best of two evils ? Our winters here are pretty cold, my thoughts were to tuck the scope in a sheltered corner of my deck, cloaked and covered with perhaps blankets or a sleeping bag, or even purchase the Green Witch cover - Cases, Bags and Covers for Telescopes and Other Optics.... I don't want to not use my scope in the winter, but I don't want to damage it either.

[Moonshane]

I agree Angelica. for me the key is that any moisture however caused, is allowed to dissipate quickly. this seems to happen quicker indoors to me and is less 'dangerous' especially if you use (as I have just made) a cover of breathable material.

[Angelika]

I agree Angelica. for me the key is that any moisture however caused, is allowed to dissipate quickly. this seems to happen quicker indoors to me and is less 'dangerous' especially if you use (as I have just made) a cover of breathable material.

What type of material did you use to make your cover?

[Moonshane]

I used two layers of garden weed matting, sewn into a circle about 4" larger radius than the tube and then with some elastic into the fold. worked a treat - just like a big shower cap really but lets air in / out. and (presumably) won't be affected by damp. I may do a thread in the DIY section. you can buy them but they are quite expensive especially for a 16" tube and as I had the material anyway.....

it will also act as a filter for my fan and prevent stray light coming up from the ground when e.g. observing in snow.

I may make one for the top too in due course.