Roll away building observatory
Having an observatory, makes astronomy a much more pleasurable pursuit, no more days of carrying all the gear outside, waiting for sunset to close in, spending a considerable amount of time doing a polar alignment ..... Only to have the clouds roll in as soon as you are ready to go. Then having to spend another hour carting it all back in again.
I have had a roll off roof observatory, which had it's positive and negative points, some you don't think about until it's built, the realization at that comet low on the horizon is not available, but it did provide considerable shelter against wind. However the shifting in of new neighbors and four floodlights shining towards my location made it in my opinion no longer worthwhile.
The telescope and mount plus considerable other bits and pieces made it's way into the lounge room, where it remained whilst I decided whether to give it all away and do something else, or build another.
9 months passed by before I made a move, I finally decided that astrophotography was still something I enjoyed doing,( plus the lady of the house wasn't overly fond of it cluttering up the house) and set about designing another home for my gear. The new observatory needed to have the following
• A small footprint, due to council regulations , smaller than 10 m2 needs no permit
• To view objects to the north at a lower altitude
• To have view of the SCP for alignment proceedures
• Generally good view of the sky
• Protection from neighbors lights
• Able to house all the computer equipment, under cover during imaging
• Enough room to maneuver around the scope
• Centrally located in a secure position
• Solid, weatherproof
• Easy to build
A roll away building fitted the criteria, however the design needed to more than just a box, something just a little different but not too complex to build... Curves were out.
Once you go into angles timber loses some of its simplicity and needs reinforcing or bracing, so a steel frame was chosen
A basic hexagon design was settled upon, a basic square floor with enough room to walk around was built, encompassing the old mount base..... Left over from days prior to having a permanent location, setup separately to the floor to enable movement around the scope.
50mm box tubing provides the frame, with 75mm box for the lower rails, I had it made offsite professionally so it was square and welded properly. Once it got so heavy that moving it was beginning to be a challenge I had it brought onsite, 12 wheels were welded to the base and mounted on rails attached to the floor. Extra steel was welded in to provide shelving and a doorway. The doorway being large enough to for the scope to fit through.
From this point a suitable material was needed to cover the frame, I wanted to use checker plate aluminum, but thermally it's not practical without insulation, similar for any sheet metal, so structural plywood was chosen. Painted properly it will provide some thermal stability, waterproof, and strong enough to walk across. It may need extra ventilation once summer gets here....... To be investigated later.
Painted a color bond green to blend in, underground power and computer cabling to enable operations to be monitored inside the house. Boat carpet for a cleanable floor. Install the scope and mount.Shelving enables the monitor to be housed at a convenient height, plus other bits.
Functional......its not lightweight, but it's maneuverable and does the job nicely.
Pics provided. Hope it gives some ideas for others.
Hi Clive, that is an excellent design and definitely has given me a few ideas.
Will you be putting in any more flooring so you can stand in the Obs and use the computer once it is rolled back or is all monitoring/imaging done from the house.
I toyed with putting in a sheet of steel grating that could be removable, perhaps just sitting on some brackets so I could stand just inside, but I have found with a few inches left I can reach the computer to set it all up without going inside the obs, it's only a foot or so high if I have to go to get something I can do without much fuss, ..... But it would be more finished with some of those gratings, I think the ones I looked at where a couple hundred each so haven't happened yet.
As for the imaging, once phd calibration is done and object located, I generally just set and forget, go back into the house and I can monitor the whole computer thing through VNC viewer, which allows me to control the obs computer from the house, however once the weather warms up I don't mind spending a while just looking through some binos or just soaking up the atmosphere of an open sky.
Thanks fred and Lester, it pretty much meets my needs at a minimum cost, the 3 pier setup does limit me to the mount I have, but it performs well enough at 1000 mm focal length, although I do like long focal length images, the weather in Melbourne is not good enough to pick and choose your nights, plus the seeing is usually only ordinary, so will leave the big stuff to such as yourselves.
Hey, a tripod is no limitation with the way youve done it, just as stable as a pier, except you have to be carefull not to trip on the legs, small point. Cant see how that limits the mount, just adjust whatever tripod you get may get in the future with a different mount to match the spacing. The cost equation youve done is interesting, given you can pack up and go somewhere else with everything anytime. I bet its cheaper than a pier and more versatile.
If its stable, and it looks so, FL wouldnt matter.
Hey, a tripod is no limitation with the way youve done it, just as stable as a pier, except you have to be carefull not to trip on the legs, small point. Cant see how that limits the mount, just adjust whatever tripod you get may get in the future with a different mount to match the spacing. The cost equation youve done is interesting, given you can pack up and go somewhere else with everything anytime. I bet its cheaper than a pier and more versatile.
If its stable, and it looks so, FL wouldnt matter.
It's stable as it sits, very much so, haven't checked the mount for PE yet, will be doing so soon as the sky clears with PECprep so I will know just how stable/ smooth it is.
The refractor, no collimation to worry about, this one has very little focuser shift, no dusty mirror, simplicity itself..... Luv it. Happy mediocrity plus it looks like a telescope, not a construction made by a committee.
Although all the big scopes/monster FL are mirrors so I can understand your affinity with them.
This is bloody great! That's given me new ideas for mine too. I wanted to do a rolloff roof but I never like the idea of having the walls left around the scope. I just love the idea of having the scope going through the door when you open and room to slew without sides limitations. Genius! Now I'm thinking of having a closed PC room in half of the obs and the other half like yours with walls and roof that will slide over the PC room, like a telescopic obs. And the telescope is outdoors on its own platform. No drama with thermal. ... and no need for a pier. Just use my tripod too as Fred mentioned. Champion!
looks like you ticked all of your boxes and have satisfied everything
you wanted. That's rare in any permanent setup. Like you said, it is
not until you complete a venture like this that you find a niggling downside
but it's all good experience, and for us builders, a lot of fun too
I have two suggestions, firstly, I used green colourbond fencepaint to
paint my dome...and green was a very hot colour in the sun.
I know green makes the obs blend in well but it's not the best choice
for me at least....i changed it to 'primrose' cream colour (Solarguard)
Secondly, I'd hate to see you come a cropper by tripping on something
near the scope and falling down the larger drop of your sloping block.
Is there any way you could incorporate a thin gauge set of handrails
on the deck?
That is a great design you have there Clive! I too had the same decision in having a permanent set-up as I only had the corner of the backyard to use and only a 2.4 x 3.0 metre area to work in. I built my rollaway out of timber which measured .900 x 1.300 x 1.500 with one end fitted with fixed wheels and the other end castors which allowed me to manouvre it to one side. Works well too!
Cheers!
Handrails don't seem to be an option due to the design, legally because it's less than 900mm they are not required, I am in the habit of exiting on the side with lowest drop... So hopefully I wont come a cropper.
Color..... It may end up changing if it's too hot, My last obs was a timber one with lots of ventilation, and it never got hotter than outside, I would probably put a solar panel on he roof and some shielded computer fans high up on the rear wall so when the suns cranking it up so are they. When it was primed ( the plywood is so smooth you have to use special primer), it was white and a bit of an eyesore visually, although that would have been the most thermal color, should I need to repaint a cream would probably be the next option.
Winter has been so long and wet that vie forgotten what warm is, I'm sure any difficulties ..... And there's always a few.... Will be resolved in due course.
I'd just like to get out and use it at the moment :-)
.
plus it looks like a telescope, not a construction made by a committee. 
