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Martin Perrett

Cheap simple easy small DIY observatory

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Hi all,

After having my mind programmed into thinking that home observatories should be round or square I saw an article showing a triangular one. This altered my thinking completely. I had some plywood and other wood left from building my house so took a couple of days to build my observatory. The size was dictated by the tripod base and the movement of the telescope on the mount. I have a NEQ6 Pro and 8inch ACF. The first thing is to align the tripod along the meridian North South with the help of the sun's shadow and the time. This means that with the scope parked it takes up less room. The roof hinges over with the help of a counterweight (not shown on my first video) and the base of the observatory is a equalateral triangle about 5-5 feet high to allow the scope to see most of the sky. This setup allows for access to the scope but is really for remote viewing. The triangular base is approx. 6 feet on each side but the roof requires room on one side to be hinged over. The observatory can be built from 4 sheets of 18mm exterior grade ply and one sheet of 5mm marine ply for the roof and 3 4.2mtr length of 50mm by 100mm treated wood. The cost could be less than £200 if you can use some reclaimed bits. The video I made is about 20 minutes long and involved me thinking and working things out while building it. The triangular construction is much easier and stronger than a square or circular one. The design means I have the scope setup and ready for those short glimpses of clear sky while also able to try remote control of the scope with the roof closed. Since the first video I have put more hinges on the joint and a beam (made from hardwood I bought as an off cut) with a couple of old rail track plates used as counterweights. The next thing is to use a garage door opener to remote the opening of the roof. 

So here is the link to the video. Please just see it as an example of what you can do, not as a 'this is the way to do it' video. If I was building it again it would be similar but better.

 

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Since making this observatory I have made the roof one piece and counterbalanced. I have also put another short video together to show the progress.

Hope this helps

 

Martin

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Going great Malcolm. The addition will stop you from getting a bad back. :)

You will certainly enjoy having an observatory. Best piece of astro equipment I have invested in by a country mile.

Steve

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So the observatory is built and now for some video of what it can see. I have already polar aligned the NEQ6 using the polar scope. Stars are not very visible at the moment due to weather!! so I used that big star seen during the day to align the scope!! Using a Windows 10 computer in the observatory with Carte de Ceil and Remote Desktop worked but I then used a Raspberry Pi model B and Kstars and Indi etc. and used Remote Desktop from a Windows 10 computer. Using this setup I can control the telescope from anywhere on the Internet. So my choice setup is a Raspberry Pi 3 running Kstars Ekos Indi and then putting XRDP on the RPi as well. Open a port through your router and control from Windows 10 Remote Desktop. The camera output is sent through a webpage (www.cornishastronomy.com and Telescope page) The camera will be remote controlled via the Internet in the future. Things to do include remote opening of the roof. The weather can be seen on www.falmouthweather.com and seen on www.cornishskycam.com or www.falmouthbay.webcam but an automatic rain sensor may be another project.

So the video shows the Sun on two occassions either side of the Meridian and used to 'sync' the scope. Then there is some longer shots of the Moon on two nights. The camera recorded the sound of the wind as it was very windy!!

Remote control of the focus is also on the to do list...

 

Hope this shows what a built observatory can do as these videos were recorded between rain showers and did not take much longer than the length of them to do.

Clear Skies

Martin

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A little while on I have made another video using 360 VR to show the observatory now. The triangle has now been expanded at one end as the bits were getting too close to the edges. I think an eight foot sided triangle would be a eter size. The roof opens with a garage door opener that has been modified and programmed to do the job. The programming of the garage door opener was probably the hardest bit!!! Using 3 buttons, a seven segment display and pages of instructions to set the direction, the speed, the force and several tens of other possibilities while opening and closing the roof to see if it had the correct effect!!! This is now set for the slowest speed with slow endings. Remote control is via a Raspberry Pi running Indi web and KStars on the remote control Windows 10 computer. This also controls via remote desktop a Windows 10 computer that runs Sony Imaging Edge software for control of the Sony A77ii on the telescope, the Hitecastro focuser and the Nextimage 5 finder scope camera which can be seen on the remote control computer anywhere in the world. Still cannot put the solar filters on remotely though!!

https://youtu.be/6eju0AY6y44

 

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