Observatory location

[Jonny_H]

Hi all,

Not sure if this is the right area for this post, so apologies in advance if it isn't.

Anyhow, I am in a bit of a dilemma and I'm not sure what to do and need a bit of assistance/advice.

In short, I have an opportunity to buy an observatory dome, but the only place I can put one is on my patio. To rephrase that slightly....the only place that my wife will let me put one is on the patio   However, what I'm not allowed to do, is dig-up the patio, drill lots of holes into it and so on... so it would literally be a case of putting the obsy straight on top of what is there (smooth Indian Sandstone).

So this brings me onto my question(s). Whilst I know it will never be as good as an observatory with a purpose made concrete base etc.... is it still possible to put an obsy onto a patio or will this be a waste of time and just be frustrating in the long run?

before anyone suggests it, I have discussed putting a shed structure there instead but the response I got was in favour of an obsy dome!

Thoughts and comments please.

Regards,

Jonny

[Peter Drew]

Provided that you can get a good view from that position I don't see any overall problem.  You don't, these days, have to be inside the observatory  during imaging so vibrations shouldn't be an issue.  The advantages of an observatory usually trump any other issues.     🙂 

[Jonny_H]

Thanks @Peter Drew

In terms of securing a dome to a base, how is this achieved? E.g. are they typically bolted down? Silicon sealed around the bottom etc....?

Thanks,

Jonny

[Peter Drew]

A dome base, typically circular, ideally should be around the same height as the telescope positioned horizontally.  The dome has to rotate so the feature that it rides on is bolted to top of the base, the dome then has to have one of various methods to prevent it from blowing off in high winds.  As far as attaching the base to the patio, cement or a sealant if the base is a bolted down design, is usually sufficient.      🙂

[Guest]

What kind of scope and mount will you be using?

[Jonny_H]

Thanks for the responses so far.

@Mike Q I currently have a SW Esprit 100ED and a StellarLyra 8" CC, both of which I use with a SW AZ EQ6 GT mount.

Initially I will be using exactly the same setup whilst the negotiations continue for me to bolt down a pier..... That said  i have to prepare for me not winning that arguement so it could be that i end up just using the standard AZ EQ6 setup in the dome!

It is worth noting that the majority of my time will be imaging whereby i will sitting inside the house, so I'm not hugely concerned about vibrations etc...

I hope this makes sense.

Thanks,

Jonny

[AstroMuni]

On 25/07/2022 at 12:21, Jonny_H said:

Initially I will be using exactly the same setup whilst the negotiations continue for me to bolt down a pier..... That said  i have to prepare for me not winning that arguement so it could be that i end up just using the standard AZ EQ6 setup in the dome!

Take a look at this advert. May give you ideas for pier

 

[Louis D]

Patios and decks in the US are usually right up against the back of the house which seems like a terrible place for an observatory.  You haven't exactly said where your patio is in relation to the house, shed, trees, shrubs, etc.

Why would your wife be willing to give up the patio?  Mine would dead set against it since she likes to sit out on the patio in the evening sometimes.  This would be difficult with an observatory plunked down on top of it.  Most folks in the US put their observatory toward the back edge of their backyard to get it far away from the house and neighboring houses.

[Jonny_H]

Thanks @AstroMuni

Hi @Louis D

You are correct re: patio location in relation to the house and this is the same with my arrangement (and most others presumably).

In short, I have a 'raised' patio which covers the entire width of the house and extends out by about 3.5m. To the side of the house the patio line continues (3.5m out from the house) but is about 1ft lower than the main patio area. We dont really use the latter space much hence why my wife doesnt mind it going there.

In terms of view where the obsy would go (and where i currently set-up my mount) - my garden is west-facing and I have reasonably clear views of the South and West. North is a little restricted and East is completely blocked.

Hoping I have explained that well enough.

Thanks,

Jonny

[Cosmic Geoff]

Don't under-estimate the effect of high winds, even close to the house. If the observatory is not securely held down to a foundation, high winds will tip it over. Just resting it on patio slabs won't do.  I have had to weigh down a plastic greenhouse and secure it to the house by a wire, to avoud a repeat of an unfortunate incident, and that greenhouse was shielded by nearby walls on three sides. 

I assume that if your wife won't allow a pier she is unlikely to agree to taking up the patio slabs. 

Maybe you could lay concrete slabs for flooring & hold-down on top of the sandstone so that the whole thing is completely reversible?

BTW I drilled a 3' x 2' commercial concrete paving slab to mount a satellite dish and found the material was extremely difficult to drill. 

Edited July 28, 2022 by Cosmic Geoff
slabs suggestion.

[Carbon Brush]

My contribution....

If drillings and fixings into existing structure are not allowed, is it assumed house moving is imminent? Or the dome is a passing whim?

The single most important part of siting an observatory is how much and what parts of the sky you will see.
From your description, it isn't that bad, at the outset.
Though I would be negotiating for the bottom of the west facing garden to give a better north view and some east view.
This is of course subject to buildings, trees etc. not yet mentioned.

I agree that you can't just place a dome on the slabs. It needs to be fastened or weighted down or it will go wandering in the wind.
Concrete blocks or slabs screwed to the dome rim will avoid damaging the patio.

The mount can be a tripod on the slabs - until you nudge it and lose alignment.
A pier could be screwed to a concrete block to prevent movement.

Paving slabs are usually extremely hard work drilling. Be prepared to buy multiple masonry bits.
Breeze blocks are less dense but much easier to drill.
Though will the 'management' like a row of breeze blocks under the dome?

In my negotiations, a shed with the roof rolling off to a pergola like structure was viewed more favourably than something that looks like a recycling bottle bank.
If you move, the new buyer is more likely to tolerate a slightly strange shed being left.

Sorry if a lot of this sounds negative. But I think it is a better approach when the project will cost you many £££ and hours.

To finish. An observatory was my best astro spend ever.

Good luck. David.

[Louis D]

3 hours ago, Carbon Brush said:

something that looks like a recycling bottle bank.

OMG, got the mental image of neighbors tossing recyclables into your observatory. 🤣

[JeremyS]

2 hours ago, Louis D said:

OMG, got the mental image of neighbors tossing recyclables into your observatory. 🤣

Better than the dog walkers’ bin I suppose 😊

Which reminds me: when my obsy was delivered (see my pic), several neighbours thought it was a new septic tank…. 

Edited July 28, 2022 by JeremyS

[Franklin]

I'd try and persuade the other half that it is completely feasible to lift enough slabs for the dome base and pier to be installed correctly and put the slabs in storage which could then be re-laid should you wish to dismantle the observatory if you ever move house. Done properly no one would ever know the observatory had even been there.

[Louis D]

4 hours ago, JeremyS said:

Which reminds me: when my obsy was delivered (see my pic), several neighbours thought it was a new septic tank…. 

When I first got my 8" Dob and used it in my front yard, passersby would ask if it was some sort of cannon. 🙄

[JeremyS]

1 minute ago, Louis D said:

When I first got my 8" Dob and used it in my front yard, passersby would ask if it was some sort of cannon. 🙄

Yes, but you live in Texas 🤣

[Louis D]

16 minutes ago, JeremyS said:

Yes, but you live in Texas 🤣

True this. And, the University of Texas (at Austin) fires off a cannon on the field after every (American) football touchdown made by their team.

 

[Jonny_H]

Hi all,

Appreciate it has been a few months since a response in this post but thought I would give an update and ask some more questions

in terms of a dome, a good offer recently revealed itself which i couldnt resist, so i took delivery of a gleaming white pulsar 2.2m dome yesterday morning. It is currently being stored in my garage until I have figured out what to do with the base/pier etc....

which brings me nicely onto my question(s)..... i am still trying to figure out what to do whilst still speaking/negotiating with the management. One 'meet in the middle' Idea i had was to install a small raised wooden decking using concrete decking footing blocks secured to some leftover sandstone blocks i have layed on top of the patio. The obsy can then be bolted down to the decking which in turn can be either cemented or botled to the large sandstone slabs. This way the main patio is untouched. thoughts on this?

For those with eagle eyes have probably spotted my remaining pain point, which is how to secure a pier??? Any thoughts?

[Trippelforge]

Can you posts some photos of the patio and sightlines? I know you said you were happy enough with what you can see, but I am just curious what it looks like.

If it were me I would probably use a heavy (100+ kg) block of concrete sitting on a very firm rubber pad for dampening. You could make one using a form / concrete mix in it's permanent location. Obviously sitting on the patio with a hole in the decking. 

 

Edited November 30, 2022 by Trippelforge

[Jonny_H]

Hi @Trippelforge

Thanks for the response.

I will take some photos of the patio, probably in the morning now.  When you say sightings, I assume you mean of the skies? I can get these over to you too, again probably in the morning to get a better orientation.

funnily enough I have just been looking at solid concrete blocks you can buy used for foundation support. Not sure on the strength/consistency etc... but could be an option. Only (I say only loosely) 35kg though so might not give enough stability!  Or of course I can make my own as you say.

Edited November 30, 2022 by Jonny_H

[Trippelforge]

1 hour ago, Jonny_H said:

Hi @Trippelforge

Thanks for the response.

I will take some photos of the patio, probably in the morning now.  When you say sightings, I assume you mean of the skies? I can get these over to you too, again probably in the morning to get a better orientation.

funnily enough I have just been looking at solid concrete blocks you can buy used for foundation support. Not sure on the strength/consistency etc... but could be an option. Only (I say only loosely) 35kg though so might not give enough stability!  Or of course I can make my own as you say.

Ya I meant what you could see from the location. Again not that it matters, I was just curious to see the new home for the observatory. 😁

 

[Jonny_H]

Understood.

I managed to dig out an old photo from earlier this year when I was testing out the camera on my mobile.

This is pretty much my Southern/South western view. My absolute western view isn't too bad but a row of houses on the parallel road starts to restrict views albeit i can still see a good chunk of sky above.  My North view again isn't too bad but my neighbour has one tall tree. I can easily see Polaris though so no major concern as I can PA  My Eastern view is really the issue and is more or less blocked by the back of my house. Moving down to the end of my garden doesn't help much and in doing so also heavily restricts my western view.

In an ideal world I would have clear views 360 degrees but we can't win them all. I work with what I've got though

 

Edited November 30, 2022 by Jonny_H