Old Observatory

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Mount View Observatory



Mount View Observatory

Three years ago I bought my wife a telescope for Christmas. Don’t think this was a cunning ploy to get myself a telescope! My wife actually asked for one as a Christmas present!. Anyway, two and half years later and the acquisition of a 10" LX200 allowed us to enjoy the occasional viewing session, however all to often we would find it to much trouble to drag all the equipment outside for what might end up as a 30 minute outing. In addition to this I was very keen to have a go at CCD astrophotography. This would mean even more equipment would be required and set up before any results could be obtained. This all led me to consider building an observatory in our back garden. I had read many post that highlighted the benefits of a permanent installation and believed this would let us gain far more use of the telescope. There were, however many reasons NOT to build an observatory in our back garden:-

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We live in Sheffield, a large city in the UK with its associated light pollution.

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Our back garden is small and slopes up from the house. Any building would be a significant feature when looking out of the house.

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The ideal place for the observatory would be the worst aesthetically, right in the middle of the lawn!

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The sky to the East is blocked by a neighbors house, compete with security light on a dusk till dawn sensor!

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Observatories don’t come cheap or at least the ready built ones don’t!

You may think this was enough to put us off. No way! We still believed the end result would be worth it (see later). I pleaded with the wife not to let me build an observatory as I knew it was going to be a significant undertaking in both time and money, but she was just as enthusiastic as me so the decision was made, we were to construct the Mount View Observatory!.

 


Construction

There were many decisions to be made before any construction could start.

Trolling the web revealed two main type of observatory design. One is the stereotypical dome and the other is the ‘roll-off-roof’ shed. Each has their merits, but in the end for us, a shed would be less conspicuous and easier to build.

Next came the decision regarding converting a prefabricated shed or building a custom design from scratch. I spent a week or so looking at the commercially available sheds with a view to converting them into a ‘roll-of-roof’ design. Eventually I realised I would not be happy unless I designed the shed myself. This had a number of benefits, obviously I could incorporate all the features I desired, but also it meant I could stage the construction to fit in with my other commitments: (work, Daughter, Wife , etc).

Then came the decision on the overall size. All the construction articles I had read stated an observatory can never be to big and not to compromise on the size. As usual I could not follow these recommendations. Placing the shed on the lawn meant I had to minimise its impact on the rest of the garden. After a bit of debating with the wife we settled on a 8 foot (2400mm) by 6 foot (1800mm) shed. I was fortunate to have a garage with a concrete floor that was ideal for production of the shed panels.

 

 

 

Before starting on the shed construction we wanted to install the telescope pier. This was a big undertaking, mainly because we needed over a ton of concrete and ballast which had to be hand carried in 25Kg bags through the house as we have no rear access for a vehicle. We also wanted to be sure we could dig a 1 meter deep hole in the lawn! As you can see I employed an able worker (the Wife) to dig the hole while I directed!

For the pier I acquired a 180mm diameter steel pipe from a local scrap yard. This was placed in the hole and held in position with 3 wooden batons. A steel mesh was placed around the pole and the concrete was poured until level with the lawn. As usual when there is wet concrete, everyone who helped wrote their name in the wet surface.

A week later the covers were removed and the pole was cleaned ready for the top plate which I welded in place after a rough N/S alignment. (I should have took more care with this but I was to eager to get it completed and did not wait for a clear night to get a good alignment!)

In July 2001 we started construction of the shed.

General details are as follows:

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Cladding from 15mm pine shiplap in 1800mm & 2400mm lengths.

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Frame from 50mm square pine at a 450mm spacing.

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Floor on 50mm square batons with 16mm tong and groove boards.

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Door from 15mm shiplap placed vertically on 50mm square full frame.

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Apex roof built as light as possible but retaining structural rigidity. This used 34mm square frame covered with 9mm plywood for the roof panels then covered with premium felt to finish.

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Six rubber 50mm fixed casters fitted to the roof frame.

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A metal channel was fitted to the top of the long wall for the casters to run in.

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A wooden skirt was placed around the roof to cover the wheels and provide additional weather protection.

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Hasp locks were fitted to the roof when in the closed position.

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Door fitted with heavy duty hinges and a high security 5 lever lock.

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Finally all panels were given two coats of clear wood preserver and then two coats of coloured wood stain, (I was under orders to paint it green!).

On a fine Saturday during August we carried the shed panels from the garage to the garden and screwed them together in less than an hour.

Lifting the roof into place looked daunting but was easy since I had keep the construction light. The wheels located perfectly in the channels and it rolled back and forth with ease, I was a happy chapie!

One of my ongoing concerns was the height of the pier, I had designed this to place the top of the scope as close as possible to the sliding roof. I could not be sure this was correct until the telescope was fitted to its wedge and pier which was still some way off.

Once the roof was on and secure I could start with the fixtures and fittings.

Power and Ethernet were cabled from the house. A carpet was laid and lighting installed. Final items were the control PC, a chair and a heater.

The PC is left running 24 hours a day to combat the any condensation that may build up in the winter.

 



I had left the external ‘roll-off-roof’ support frame until last. This was the moment of a significant design change! My original plan was for the roof to slide off to the North, thereby giving an unrestricted view of the Southern horizon. When the time came to construct the frame I soon realised a Northerly frame work would be almost impossible to build. This was because our garden slope significantly down to the house in a Northerly direction meaning the vertical supports for the frame would be over 4000mm in length with no way of reaching the tops of the poles. Fortunately I had designed the roof to slide either way and also kept the apex relatively low. The decision was made to place the frame at the Southern side of the shed which allowed very straight forward construction. I increased the length of the runner to allow the roof to clear the end of the wall by 400mm thereby giving a clear view of my Southern horizon.

The frame was constructed from 75mm square fence posts with 75mm by 50mm rails for the metal runners. A cross brace was fitted to the far end. Once again the entire assembly was preserved and then painted green.

After a few careful adjustments to the roof side skirts it was time to test the sliding of the roof. This was quite a concern but in the end worked as well as I had hoped.

In operation I can un-hook the four roof hasp locks and manually slide off the roof from inside the shed within 1 minute. Closing is easy too, grab the end of the roof and pull it back over the shed. Then remember to fasten the hasp locks.

We have a number of very wet and windy days, up to now there has been no leaks from the roof or its fitting to the shed. I had plans for various additional weather proofing fitting that would requiring placing around the roof edge each time it was used. Fortunately these do not seem to be required.

 

The moment of truth came when I fitted the telescope and wedge to the pier. There was 50mm of clearance exactly as planned!

You can see from the photo I am currently using a home made wedge. There is a construction article elsewhere on the website. For now this is adequate, however I imagine I will purchase a secondhand Meade Super Wedge when one becomes available.

Final tidying up is now complete, most of the scope cables run under the floor and the PC has the scope control software and camera software installed. I can be up and viewing in 5 minutes and CCD imaging in 10 minutes.

I would absolutely recommend building an observatory to anyone who does not have the time and patients to drag outside, set up and align the numerous components necessary for astro photography. Even for viewing at the eyepiece, being able to walk outside and power up the scope within 5 minutes of noticing clear skies is incredibly convenient. And when it comes to packing up, an observatory really make the difference. I used to hate being tired and really cold and spending over an hour packing away each of the components.

In the few months that the observatory has been in commission, I have already spent more hours viewing than in the past year.