Storing equipment in your observatory. (Temperature and humidity)

[George Gearless]

Hey guys.

I'm in the (very) early stages of planning my very own home observatory. I've got loads of questions, but particularly one is very important for my further planning. Heating and/or dehumidifying.

Do you heat and/or dehumidify your observatory? If you do heat it, by what means do you do it? Is dehumidifying your observatory enough to protect electronic equipment and optics, or is heating required if you live in a place where the temperature regularly drops below zero in the winter (I live in Denmark)?

I'd be interested to hear from people who live in a similar climate on how you've solved this problem.

 

[JeremyS]

I’ve been operating my Pulsar domed obsy for 19 years. No heating, no dehumidifier, no problem. I leave the dew heater on the C11 and the heater on the GoTo controller, on permanently, though.

Edited April 11, 2023 by JeremyS

[Saganite]

The Jury is still out on the need for  a dehumidifier in my Pulsar dome.  I constructed an octagonal marine plywood base with fine mesh air vents on every side, and left  one third of the 400mm hole in the centre ,around the pier, open.  Add to this the open air gap between the walls and the rotating dome, and there seems to be more than enough air flow to keep the inside dry.  In six months of use I have had moisture on the AZ100 and scopes on just a few occasions, so I am not sure yet.

Like Jeremy, I have kept dew heaters on permanently set low through this winter.

Edited April 11, 2023 by Saganite

[Budgie1]

I live on the West Coast of Scotland, so high humidity most of the year, high rainfall and temperatures from -6°C in the winter to 26°C in the summer.

I've only had my ROR observatory over this last winter (build thread is HERE ) and I haven't suffered any issues so far with moisture. There is a large enough gap between the walls and roof to allow good airflow and this keeps the inside dry. Even on nights with a lot of dew, the mount, scope & camera are normally dry again by mid-morning on the following day.

I have two scopes I use on the mount, Evorstar 80ED DS Pro and Evostar 100ED DS Pro. When they are not being used I have them stored in a Oklop padded bag with a Desiccant Cap in the focuser to keep it all dry inside the scope.

I've just fitted a pair of solar powered fans to help remove some of the heat from the roof in the summer. I'm not sure how well they will work, but it's worth a go and the fans also add to the circulation of air during the day.  

[Graeme]

My roll off roof observatory is still in the construction stage. (Here) The plan for environmental control is to use an Arduino and DHT11 temperature and humidity sensor to turn on fans when the temperature gets too hot and heaters for frost protection. To prevent condensation you need to keep the temperature 2 or 3 degrees above the dew point so I'm thinking of using a fan heater for that. Martin's (above) solar fan idea is good because it is fully automatic and can be installed high in the gable end of the rolling roof section. I'll probably copy that one!

What type of observatory are you planning?

Graeme

Edited April 12, 2023 by Graeme
For Shameless self promotion.

[George Gearless]

14 hours ago, JeremyS said:

I’ve been operating my Pulsar domed obsy for 19 years. No heating, no dehumidifier, no problem. I leave the dew heater on the C11 and the heater on the GoTo controller, on permanently, though.

Well, you really can't beat practical experience. Which was why I posted my question here :).

I'd just like to make sure that I'm on the same page as you: I plan to have an older laptop, my Stellarmate, cameras and other electronic equipment, fitted and 'ready to go' at the roll of a roof. You have had no issues with simillar equipment?

[JeremyS]

1 minute ago, George Gearless said:

Well, you really can't beat practical experience. Which was why I posted my question here :).

I'd just like to make sure that I'm on the same page as you: I plan to have an older laptop, my Stellarmate, cameras and other electronic equipment, fitted and 'ready to go' at the roll of a roof. You have had no issues with simillar equipment?

I take my CCD camera in each night.

I’ve had 2 old (XP) laptops continuously running in the dome, one for 9 years and another 8 years. They have never been inside.

[George Gearless]

9 hours ago, Budgie1 said:

I live on the West Coast of Scotland, so high humidity most of the year, high rainfall and temperatures from -6°C in the winter to 26°C in the summer.

I've only had my ROR observatory over this last winter (build thread is HERE ) and I haven't suffered any issues so far with moisture. There is a large enough gap between the walls and roof to allow good airflow and this keeps the inside dry. Even on nights with a lot of dew, the mount, scope & camera are normally dry again by mid-morning on the following day.

I have two scopes I use on the mount, Evorstar 80ED DS Pro and Evostar 100ED DS Pro. When they are not being used I have them stored in a Oklop padded bag with a Desiccant Cap in the focuser to keep it all dry inside the scope.

I've just fitted a pair of solar powered fans to help remove some of the heat from the roof in the summer. I'm not sure how well they will work, but it's worth a go and the fans also add to the circulation of air during the day.  

I'm looking at a simillar build of observatory. Although, I've "invented" a lever system for the roll off roof, so that when it closes it rests firmly on top of the wall frames, thus eliminating the gap. I thought it would be desirable to have the build as airtight as possible to protect equipment from the outside. Now, with the responses I've gotten so far, I'm not so sure anymore.

Your observatory looks absolutely amazing. This is what I picture inside of my head, when I think about my project. Mine might be a bit larger when finished, because I plan to build it in the corner of the garden where there is a natural 3X3 meter stone terrase. But basically, it's the same idea. 

Thankyou for your helpful response. Gave me something to think about.

[carastro]

I have had a sky POD for 13 years.  It leaks at the pivots and so l have a bucket to catch the leak but there is always some degree of splash on the floor after a heavy downpour.    I don’t remove my scopes or cameras unless changing my rig which isn’t that often.   There is a small natural gap between the dome  and the walls.  
 

In the winter months l use a dehumidifier intermittently but when l do l pad out those air gaps with pipe lagging  to save me dehumidifying the entire neighbourhood.   I have never felt any moisture on the scopes and the cameras seem to be unaffected.  I even leave my laptops out there when doing multi night imaging.  

l bought my dehumidifier from DryItOut  

Carole

Edited April 12, 2023 by carastro

[George Gearless]

2 hours ago, Graeme said:

My roll off roof observatory is still in the construction stage. (Here) The plan for environmental control is to use an Arduino and DHT11 temperature and humidity sensor to turn on fans when the temperature gets too hot and heaters for frost protection. To prevent condensation you need to keep the temperature 2 or 3 degrees above the dew point so I'm thinking of using a fan heater for that. Martin's (above) solar fan idea is good because it is fully automatic and can be installed high in the gable end of the rolling roof section. I'll probably copy that one!

What type of observatory are you planning?

Graeme

I'm thinking along the lines of what Budgie1 has done (roll off roof, self build). I'm not sure I can match his building skill. But that's where I'm heading. 

So if I've understood you correctly, you do intend to keep the observatory heated (above dew point, that is)? This is where my problem lies. If I am going to heat it, I'm going to have to insulate it vigorously. I'm also going to have to make it as airtight as possible. All of this increases the cost. It also makes me worry about the powercosts over the winter.

[Owmuchonomy]

You need two things, good airflow and some quality thermal insulation.  Build those into your plans and you'll be fine.  We have both those in our 6.4 metre dome and there is never an issue with humidity. We have various electronic devices stored in there without issue.

[Graeme]

6 hours ago, George Gearless said:

So if I've understood you correctly, you do intend to keep the observatory heated (above dew point, that is)? 

Yes, but, the heating is only frost protection and anti condensation. Condensation only happens when ambient temperature drops below the dew point. That will happen all the time when you point your telescope up towards the stars, it's not such a problem when the roof is on. Air movement is key so I'm going to use fan heaters. If Trevor the weather forecasts really cold temperatures I'll bring my stuff indoors.

[Clarkey]

I haven't had my observatory long, but so far, no issues with my set up. I have a vent fan running 24/7 (small 7W shower extractor) which only gets switched off for imaging time. If it is a cold frosty night (most of them in Penrith during the winter), I put a dehumidifier in the observatory for a few hours when shutting up in the morning. This helps melt / absorb the frost.

I leave the two mini PC's on permanently to prevent them getting damp - but everything stays put. 

[George Gearless]

On 12/04/2023 at 16:28, Graeme said:

Yes, but, the heating is only frost protection and anti condensation. Condensation only happens when ambient temperature drops below the dew point. That will happen all the time when you point your telescope up towards the stars, it's not such a problem when the roof is on. Air movement is key so I'm going to use fan heaters. If Trevor the weather forecasts really cold temperatures I'll bring my stuff indoors.

Ok. Thanks for your replies.

I have to admit that looking at you and Budgie1's observatories stirs ambiguous feelings in me. On the one hand, I'm getting a feeling of trepidation because it's such a vast undertaking (for me). Sure, I can rotate the tires on my car and do small electrical jobs around the house and such. But to build a roll off roof observatory from scratch, is beyond anything I've ever done before. On the other hand, I'm also exited at the prospect of just having to unfasten a few clamps, roll off the roof, and start 'shooting stars'. That's the dream.

I'll be following your build thread for sure. It's looking great so far and only ignites my enthusiasm over the project even more. Despite my trepidaton .