Peeking above for what?

[MiguelMJr]

I am wondering why nearly all the telescopes that I see on the net are placed so that their objective lens is "peeking" above the walls of their (roll off roof) observatory?

Wouldn't it be better to have the objective lens slightly below the walls of the observatory in order to eliminate the possibility of stray light from nearby street lights and the such from entering the scope?

Thanks,

Miguel

[ronin]

The catch is that then you are effectively in a "tube" looking up and so the view is more limited - aim the scope down a bit too much and you are looking at the observatory walls.

I suppose the other is that you then need higher walls around the sides, and also we have lights that are effectively well elevated and shining down those will always get at the open end of a scope and cause potential problems. When you look at a "proper" observatory the scope is looking through a narrow slit in effect.

Add everything up and I would say that just sticking the scope out above the sides is simply the easiest option and accept whatever the negative aspects are.

[baggywrinkle]

Plus if below the upper sills with a body inside the box there can be quite a lot of heating effect which could generate local warm rising air currents.  Above the sill it should be in relatively clear air.

It is quite amazing how much heat and mositure we humans can generate. When I have been invloved in calibration lab design we placed a limit on the number of sweaty bodies a room's air con could handle.

[Gina]

Yes, there are certainly advantages to a dome but also disadvantages, particularly for many cash strapped amateurs.

Thought - a DIY mini dome for my remote controlled widefield imaging system would be an interesting project   I wonder...

[MiguelMJr]

The problem I have is that there are many bright lights (small emergency hospital parking lot) just two lots over and to the north of my property looking down on my proposed observatory site. The worst part about it is that to my north, not too far past the hospital is nothing but the ocean and dark sky.

I guess I could build an extension to the north wall that I can raise to block the light and still have three walls below the scope which would allow clear air to run over the scope.

It would probably be a good idea to "test out" my observatory site before building the structure, right?

Miguel

[dwc]

I guess I could build an extension to the north wall that I can raise to block the light and still have three walls below the scope

This is what I do. I have panels that I fit to the North and North West once the roof is open to obscure a clues by street light. The panels slot into grooves and are joined at the corner by magnetic cupboard catches.

[Gina]

Yes, there are certainly advantages to a dome but also disadvantages, particularly for many cash strapped amateurs.

Thought - a DIY mini dome for my remote controlled widefield imaging system would be an interesting project   I wonder...

On looking at it, a dome would not suit the mini observatory due to the offset of the imaging rig on the NEQ6.

[Stu]

On looking at it, a dome would not suit the mini observatory due to the offset of the imaging rig on the NEQ6.

Gina, there's a big part of me which is relieved by that news..... I think you have enough projects on the go ;-)

Get yourself better and have a lovely Christmas and New Year

Stu

Sent from my iPhone using Tapatalk

[Gina]

Thank you Stu   If I can get through Christmas I shall be much relieved.  Hopefully next year will be a much better one

You have a great Christmas and New Year too

[laser_jock99]

Occasionally one has a need to look lower at the horizon. These are usually special events like passing comets which are 9 times out of 10 in the worst possible place in the sky. It's nice to be able to point the scope in any direction that might be required.

I specifically made my obsy pier maximum height as I have a nice southern horizon!

[Liquid360]

I seriously love seeing photos of personal observatories! They're just so personal and quite telling.

[Davey-T]

Yes, there are certainly advantages to a dome but also disadvantages, particularly for many cash strapped amateurs.

Thought - a DIY mini dome for my remote controlled widefield imaging system would be an interesting project   I wonder...

You're going to need a bigger printer to print a dome 

Dave

[Gina]

You're going to need a bigger printer to print a dome 

Dave

I'm working on it

[ollypenrice]

Not having any LP to fight against 

... I take the opposite view and have made all our observatories with rolling roof and upper sides with flaps which drop down to open the end upper wall. On the nattiest of these, the robotic shed built mainly by its owners, the flap is cutely raised and lowered by an extended arm and roller so the movement of the roof lowers the flap automatically. This almost invariably makes people laugh!  A couple of examples from when they were under construction;

If, due to LP, you'd like a dome style observatory with opening aperture slit it doesn't have to be dome shaped. Domes are very hard to make and sometimes lack headroom where it is needed (around the scope.) You can make a square shaped total rotator perfectly easily and if space is at a premium then a pod for the PC can be added to one wall.

Olly

[Gina]

My observatory is similar with the top part of the walls being part of the roof structure and a wall flap on the end wall.  Currently it's all operated manually though I have had the roof motorised and plan to again but I need to do something different for the flap.  I like the idea of connecting it to the roof with arm and roller but I can't see how to do that with my roof arrangement.  Instead I'm thinking of raising a sliding panel up and down like a sash window with cords over pulleys and motor winch.

The new mini obsy is probably going to be similar - it won't be a dome, that was just a flash thought   There is an LP problem sometimes from the neighbour's flood light though   I may need to arrange a screen.  Fortunately the light is to the west and they rarely have it on late.

That dome thought was in line with my extreme projects ideas

[MiguelMJr]

I was thinking of making my observatory something like Harry's of Harry's Astro Shed fame. I'm not getting any younger and pushing and pulling things around is getting harder with each passing day. 

Still undecided on what type to make, there are so many good ideas out there. 

Harry's Astro Shed.....

Miguel

[baggywrinkle]

The problem I have is that there are many bright lights (small emergency hospital parking lot) just two lots over and to the north of my property looking down on my proposed observatory site. The worst part about it is that to my north, not too far past the hospital is nothing but the ocean and dark sky.

I guess I could build an extension to the north wall that I can raise to block the light and still have three walls below the scope which would allow clear air to run over the scope.

It would probably be a good idea to "test out" my observatory site before building the structure, right?

Miguel

How about making a wood framed and carboard mock up with the heights you think you need? Then see what sort of viewing angles you get.

[MiguelMJr]

I have to make up my mind soon as to what I want to have built and get working on a CAD drawing and materials list. I need to have it built strong so as to be (hopefully) hurricane proof.

Here is another nice small observatory, can't remember where I downloaded it from.

No dome for me as they are generally better suited for alt/az mounts. Photo from Greene Island Observatory.

Good Idea baggywrinkle.

Miguel