1st December 2024. An apology and OMG a new idea!

 ~*~

  Sorry to those who are following my blog. Or found their way here by accident. Perhaps hoping for tangible progress on yet another, completely mad observatory or telescope scheme. Sadly I have lost interest in all my projects again. Since my wife died a little over two years ago I cannot sum up the enthusiasm to do very much at all. Every option seems to be insurmountable!

 Despite being skinny, fit, eating properly and very active I had a three hour operation on my blocked heart arteries in June 2024. So I have to take a load of tablets every day and have four stents. I have recently been through a course of physiotherapy to rehabilitate myself. More exercise classes to follow in the new year. I continue to cycle long distances on my e-bike. Weather permitting. More of an escape than anything else.

 My large back garden is completely hopeless for astronomy. The house is on the southern border and there are tall trees and hedges, literally on all four sides. 

 The idea of placing any telescope housing in front of the house is proving far too difficult. There is precious little room and any building would badly obscure the lean-to greenhouse and block the sunshine.

 I still have crazy ideas. Like building a platform. To house an observatory. With the floor at eaves height in front of or beside the house roof. Would I ever manage to build it? Who knows? Let's say it is highly unlikely.

My previous attempts to put trailer pilot wheels on a tall pier proved unstable. Too risky to push a loaded pier from the security of the back garden the 130 meters along the drive just to find the low sun. At 77 I no longer feel immortal and am unable to carry. Let alone lift 30kg telescopes above head height!

 Hang on: Let's be more realistic: Just for a change: I have just bought a smaller trailer. To match my smaller car. Even loaded with firewood logs it is so easy to push and pull around. It would make an excellent but portable base for a telescope pier. 

 The mesh sides are bolt-on additions. For carrying bulky garden waste and logs and are removable. Bringing the side height down to 33cm. The telescope will never hit the sides in normal use. See the red lines.

 I would not want to be using the same trailer for astronomy. Lifting massive piers and heavy scopes into the trailer. Every time I want to use them. Is now beyond me. Besides, the present trailer is usually busy. Or left half full of something prior to emptying.

 The cost of buying another complete but basic trailer for astronomy is not too exorbitant. Not in comparison with the price of the astronomy kit it will support! I'd probably have to add outriggers to kill any wind rock. Would I be imaging in very windy conditions anyway? Highly unlikely.

 The astro trailer would be towed slowly to the end of the drive. With the telescope already fixed on its mounting on the pier. For a clear view of the sun over the surrounding fields year round. There is plenty of room to park there undisturbed.

 A normal pier height is all it would need. Not some towering edifice needed for observing at high altitudes from the ground. The trailer adds almost two feet in extra height. Well, 55cm to the bed level actually. Just measured. A solar imaging scope doesn't need me praying on my knees. Squinting upwards for inspiration.  

 I have a massive cast iron pier from an old drawing board stand. 130cm high or lower on demand. It would just need a sturdy flange to support the equatorial mounting on top. Add a coat of white Hammerite paint to stop it absorbing solar heat. 

 Clamp the massive base in the middle of the trailer bed. I'd have to use my chain hoist and an A-frame of ladders to get it off the ground. It is ridiculously heavy! So I am barely able to roll it around on the parking area using the base as a makeshift wheel. I should use the sack truck but it is an awkward lift.

 The car battery could provide power for the imaging laptop and the mounting drives. I would be outdoors while I am imaging but that's not the end of the world. It gets cold here in winter but the dome slit used to collect whatever cold wind was blowing. I could just sit in the car! OMG! Have I finally found a realistic option for solar/lunar imaging? 

 Potential problems? There are always things I haven't thought of!

Telescope or equipment detachment underway along the drive? I'd just have to secure it for the journey along the drive. So I won't be going far. No potholes!

 Polar alignment? Mounting and drive software dependent. 

 Meridian flip? No, daft filter extension hanging of the back of the telescope. Two 2" star diagonals can send the filter stack back the way it came. Over the top of the OTA.

 Tilting of the parked trailer? Which would tilt the equatorial mounting's base and axes. This can be overcome with a builder's level and outriggers. The "parking" area is fairly level. A little experimentation will ensure I park in the flattest area. With the car arranged to avoid thermal plumes rising across the incoming, solar light path.

 Weather exposure of the telescope/mounting/equipment when parked in the back yard? We could be back to the calf hutch as a fixed garage. This would take care of security too. Or I build a proper garage with all the materials from the observatory build/demolition. I need a garage for my veteran car anyway. I'd just make the garage long enough to take the trailer as well. I have had no good reason to complete the demolition of the observatory, until now.

 

  ~*~

11.08.2024 Back to hutch one: Calfotel XL-2?

 ~*~

  Sunday 11th. Warm, sunny and breezy but with rather a lot of cloud.

 During the night I worked out how to provide inverted, raised rails. For two calf hutches to roll apart. I clearly saw two calf hutches separating in my dreams. To provide the observation slit for the twin enclosures. 

 Then I woke up. To realise that these enclosures are poorly designed. To join each other, face to face. Which is only fair. They weren't thinking about idiots like me. Dreaming about making ridiculous observatories out of them. 

 So then I had to start worrying about interfacing them for full weather protection. Only to realise that the two would be over four meters long when conjoined. Longer still when separated. The greenhouse would never see the sun! 

 Which was a bit of a shame. Because I was already laminating Baltic birch plywood reinforcement at their intersection in my daydreams. 😳 

 So I must make do with one hutch and do it sensibly. Just for a change. Size matters, but they all taper inwards at the top. The same headroom but less likely to blow over. Greater stability. Not to mention reduced material consumption. It also makes for an attractive appearance.

 The CalfOTel XL-2 is interesting. L= 226cm x Width 166cm x Height 155cm. Larger and designed to house two calves side by side. It provides enough enclosed space to be able to enjoy greater wind protection. Provided it can face south. 

 Rolling it off to the west would immediately expose the telescope to the prevailing wind. Though the hutch might offer some protection by its sheer bulk. It would make the housing of the telescope easier. Though now at £1000 equivalent. 

 Morning imaging with the sun to the east. Would mean the hutch need not be rolled back so far. Offering a useful advantage. Which is lost when imaging to the south or west. When one of the narrower hutches would do just as well. 

 Rolling the larger XL-2 hutch off to the north might cramp the nearby drive. Or it would soon run into the greenhouse! I have just 4m to play with. Depending how harsh I am with the hedge clippers on the beech hedge.

 I am imagining twin doors covering the open front. Now facing south. Though the design of the existing hood is a problem. It severely limits the altitude to which a housed telescope could point. Summer around mid day means 55º. 

 Which would mean taking a jigsaw to the front of the hutch and then reinforcing the enlarged opening with laminated plywood. To which the doors [shutters] would then be hinged. Doable? Needs further thought.

 XL-2 raised on rails? Make the headroom of the hood [say] 2m. Roll off the enclosure back by 1m? It would mean a scale drawing to be sure but summer mid day is the worst case scenario. The rest of the time the telescope would have enough shoulder and headroom. 

 The downside is the telescope is now invisible if I want to sit in the greenhouse. I would have to have a security camera and screen to check for collisions and cable tangling. Or, I could sit in the back of the enclosure. With the imaging monitor mounted on the pier. As I have been doing for several years in the 3m dome. I'd move my chair to the east or west side. Depending on the angle the telescope is pointing. 

 Whoops! Doing a Meridian flip could be an absolute disaster! Unless I provide enough headroom! The telescope usually goes vertical during the flip. A flip could be carried out manually. Without the telescope trying to lift the entire observatory off its rails! Now imagine it does an automatic flip while unattended. Setting limits on a mounting may cause further problems. Can I allow enough clearance for the telescope to go vertical? By rolling back the enclosure enough? The mounting must be clear of any overhang. 

 The obvious solution is not to have meridian flips. A fork mount and a bent [astrograph] pillar both avoid the problem. Turning something like a CEM120 into a fork is rather pointless. The declination axis isn't designed to be somewhere else entirely. Can the CEM120 be fooled into working with a bent pillar or pier? That's not an everyday question for Google. 

 I used Perplexity AI to discover that the XL-2 weighs 135kg. Or 287lbs. No lightweight then. Yet a YT video shows it being moved, tipped and lowered manually by an elderly gentleman. ChatGPT suggests the XL-2 weighs only 69kg. That better matches the effort the YT "actor" was putting into it. 

 I emailed the CalfOTel company. Only to find my contact on leave until the end of the month! I'll try asking one of their dealers.

 

  ~*~

8.08.2024 And then it was folded. [Updated 28.10.24]

 ~*~

 

 Thursday 8th. I am expecting a parcel with the Bresser 2" star diagonal today. Now I can start playing with optically folding the 150mm/ 6" f/10 H-alpha refractor. I hope I have enough 2" extensions to lift the filter stack clear of the main tube. I need some of my modest stock for spacing the stack components correctly. Each star diagonal has its own minimum light path distance. Due to the physical dimensions of the body which supports the 45º mirror. This is unavoidable.

 Some of the Lunt stack Modules are very bulky. The pressure tuned etalon is the largest. With the FT focuser a close second. Which will mean the optical axis of the modified filter stack. Has to be lifted even further away from the 6" objective's optical axis. Further increasing the demand for a shorter main tube. Just to ensure the correct optical spacing. Though with the added benefit of an even shorter instrument overall. 

 I would like to retain the primary FT focuser with its Baader Twist-lock clamp. This will provide stability and fine adjustability of etalon distance. The second Lunt-FT focuser is part of the original MT filter stack. Providing fine focus adjustment for the ZWO camera. It cannot easily be removed because of the unique interfacing with the etalon module. Will I run into vignetting problems? We shall soon see!

 Image left: First trial at optical folding using 2 x 2in star diagonals. No real attempt at getting the spacing precisely correct. Just ensuring it all fits together. There is a non-standard diameter on the front, Lunt etalon stub. I had to use my lathe to turn the inside of a 2" extension. Then groove it for the bronze clamping ring. This is the 2" Omegon extension.

 There is a Lunt 12mm, straight-through, blocking filter. Hidden inside the long extension just behind the second focuser. Most blocking filters are housed in solar diagonals.

NOTE EXTREME DANGER OF THE HEAVY LUNT COMPONENTS COMING APART AT THE PUSH FIT JOINTS!! The filter stack MUST be firmly bracketed to a main tube ring for safety. [Simulated with a spacer but not properly implemented in the image alongside.]

 Folding has saved roughly 44cm/17". On the length of the previously cantilevered filter stack. The folded OTA length is now 132cm. The straight version was roughly 167cm. All provisional measurements prior to exact spacing. Quite a saving in length. Making the OTA easier to house and to mount.

 I found the folded arrangement VERY unstable. Provided it is firmly attached to a main tube ring it should be manageable. Without adequate support there is extreme danger of thousands of pounds/dollars worth of equipment. Literally dropping like a stone onto the floor or the ground! You have been warned! 

 My original no-name 2" star diagonal has only one compression screw. Three screws would be much safer. To stop the whole assembly from rotating or falling out! The offset of so much weight 3.32kg or 7lbs makes the OTA want to rotate about it own axis. I shall probably invest in another Bresser 2" star diagonal if I can test the new optical layout somehow. I currently have no useful mounting. 

 Note that shortening the telescope by folding means the main tube must be shortened. Otherwise the focus will be within the H-alpha filtration components. Or even before them! It is difficult to judge how much main tube shortening is required with a simple tape measure. The exact positioning of these components is vital to a sharp, monochromatic image. 

 The spacing between the reflecting surfaces of the  two star diagonals  "X" is the vital thing to measure. This is the method of shortening and is unavoidable. Or the later sections of the filtration stack will not physically lie outside the main tube.

There is also the matter of the main tube baffles and possible blocking of the full diameter of the light cone from the objective. Fortunately the primary focuser is oversized. The choice of 2" star diagonals was also deliberate for the same reason. To reduce the risk of vignetting.

 Taken to extremes I could fold the entire 150mm/6" f/10 telescope. Using the same optical flats I used for my 7" folded refractor. Then the main tube becomes redundant. I could use Porsa aluminium profiles. Like I did with the 7"/180mm refractor. While the weight would not be very different from the straight filter stack telescope the reduction in length is very important for stable mounting. Moment = Mass x Distance from the pivot point. Adding more optical surfaces increases the risk of dewing and light loss at each reflection. The latter is not usually a problem with large aperture, solar telescopes.

 

  ~*~

7.08.2024 Swing that CAT?

 ~*~

  I wrote a lengthy post yesterday on options for housing my large solar refractors. Then deleted it when I had completed a new post on folded refractors. Folding my 6" optically would shrink it to far more manageable proportions. 

 The overlong H-alpha filtration on many modified, solar refractors is an acute embarrassment. Such a long stack makes it very hard to avoid sagging along its length. Though threaded fittings are stiffer. Most of us have to make do with push fits. Usually 2". Which is stiffer than 1.25" or T2.

 Shrinking the length of my 6" makes it much easier to house. Whether sitting permanently in an observatory. Or cowering under a run off cover. Observatory size is a very serious issue. No least on price. It also eats up the garden space when this is important. As it is to most of us.

 My back garden was no-man's land when I was building my foolishly tall observatories. Just to see over the hedges and my house. The latter sits unfortunately close to the southern border of my rural garden. The front garden is further reduced in width by the 7m long, lean-to greenhouse. So I have a strip of front garden only about 3.5m deep to play with. 

 Bounded by a beach hedge between myself and my neighbour's grassy paddock. I want to be able to push between the greenhouse and the proposed observatory. How else will I reach the glass? Besides, it is a long walk going right around the house. Just to reach the other end of the greenhouse.

 I could sneak a few more centimeters if I cut down the hedge and put up a fence. Not a good idea! The fence panels would warm in the sunshine and produce strong convection currents. Right in front of my telescopes. 

 The beech hedge is also more natural in its rural setting. Storms could easily damage a fence. Which the beech hedge would simply shrug off. The hedge is also a useful wind break. It filters the wind rather than accelerating and directing it. The height of the hedge is now mine to choose. The birds tell me they would much prefer a hedge.

 All of which brings me to the choice of accommodation for my telescopes. Let us suppose that the Pulsar 2.7m offers 2.5m internal diameter. The 2.2m only 2m Ø of clear space inside. A German equatorial mounting [GEM] swings the telescopes well off to each side. Rather than simply rotating and moving up and down like a fork mount. So it is no use [mis]calculating the required observatory size by telescope length alone. The telescope does not usually span the full diameter symmetrically.

 The swept volume of the extremities of the telescope[s] is an oval [lobe] on either side of a GEM. Because of the instrument's considerable offset relative to the Polar Axis [and the pier.] If there is a long filter stack, or useful dewshield length on a refractor, then this must be allowed for. 

 Ideally, one would mount the telescope[s] in an open space. Then drop a weighted line from the tip of the dewshield. Or from the camera on the end of the filter stack. Then mark out the shape on the ground as the telescope is swung from east to west. There would be a vertical component, of course. At least the clear diameter required for a cylindrical observatory [and dome] will be much better understood. 

 The height of the telescope dewshield, as it swings upwards, is also an issue. Requiring that the telescope's height be carefully arranged.  So as to be concentric to the dome's inner circumference. Otherwise the dewshield will strike the inside of the dome at certain elevations. Possibly at the zenith if the mounting is raised too high. The GEM's offset lobes to left and right must also be kept in mind. So the pier and thus the mounting height becomes vitally important parameters too. 

 The OTA can usually be slid along on its dovetail plate. Or through the mounting rings. Provided balance is achieved. Then a bias towards the lens or the focuser end. May help where tight clearance issues arise. Adding a weight to one end of the OTA can correct the balance if required.  Though care must be given to off-centre balance problems. The balance of the telescope on the mounting may change considerably. With different telescope orientations. Causing problems with tracking. Or even motor stalls on slews.

  

 ~*~

6.08.2024 Folding refractors:

 ~*~

  Tuesday 6th. Folding the 150mm/6"? 

 There is always the option of folding both refractors into more compact shapes. This reduces the size of the housing or observatory required. As well as helping the mounting. Many of which struggle with lengthy telescopes. Not due to the weight but due to their moment. Which is a term used in physics for mass [M] x distance [D] from the pivot.

 There is usually a heavy component at each end of a refractor. The objective in its metal cell and the focuser at the other end. This effectively doubles the moment. Since the majority of the weight is so far from the pivot point. [Mounting axis.] Add the considerable length of the filter stack and things get even worse.

 Classical refractors are normally of much greater focal length than modern, Newtonian reflectors. Though the tendency is towards faster [shorter] APO [apochromatic] refractors. Which often use special glass types to correct the false colours. From which normal achromatic refractors suffer. Which historically meant very long and unwieldy instruments. If only to overcome false colour.

 These older designs have a very high moment. Demanding large and heavy mountings. Often made of heavy cast iron. With very large slow motion gears.[wormwheels.] This made them unsuitable for amateur use. For those not rich enough to own a large observatory. The modern amateur often carries all of his equipment outside for each observing or imaging session. This demands light weight and compactness.

 I had already built a folded version of my 180mm/ 7" f/12. The same could be done for the 6". In this case only folding the tail end at the very beginning of the very long, H-alpha, filtration stack. 

 Two 2" star diagonals and a suitably long extension tube. Used as a spacer between them. Would probably do the job. To bring the filter stack parallel and close to the outside of the main tube. But pointing forwards towards the objective. The star diagonals safely avoid worrying about collimation. It is automatic thanks to the 90º bending of the light. By a mirror in a precision housing.

A main tube ring and connecting link could easily steady the folded stack. Though slight linear movement must be allowed for during focusing. A typical, felt lined tube ring need not be tightened unduly. So that it can slide freely along the main tube.

 The main telescope tube of the 6" might need shortening slightly. Or the FT focuser removed altogether. The distance from the focus to the Lunt 60MT etalon is critical. The primary focuser was useful for making these fine adjustments. Often in the hope of improved images.

 The ridiculously long, cantilevered, filter stack was already an embarrassment! I had to provide support in the form of a rectangular, aluminium tube. Not easy to attach to the stack. Because of the need for linear movement and the rotation of the OTA over time. Sagging of the multitude of push fit elements is almost inevitable!  

 I only have one [no name] 2" star diagonal. So I have ordered a Bresser 2" star diagonal. To experiment with possible folding arrangements. The Bresser has "only" 93% reflectance. Compared with the usual 99% claim for the dielectric diagonals. Which hardly matters with the intense solar energy available in a 6" refractor.

_____________________

 My 180mm/7" badly needed remote, screw adjustment for the 2nd folding mirror. Bringing the adjustment back, via rods, to suitable knobs on the telescope back plate. Without which collimation was a nightmare! I went back to the straight tube version instead. Before finally giving up.

 My massive mounting struggled with the weight of two [or sometimes three] OTAs. All down to the weak worm housings. The Ioptron CEM120 could probably manage both 'scopes by weight alone. Though only if they were optically folded. Folding has the advantage of greatly reducing the moment of a telescope.

Moment = mass x distance from the pivot point. If the mass doesn't change. Then the moment is reduced by bringing it nearer the pivot. i.e. By physically shortening the telescope. Though there is usually some small increase in overall mass due to added components. The distance at which the weight lies from the pivot is more important than the weight. The classic big kid, little kid on the seesaw.

 The moment of an equatorial mounting can be similarly reduced. By using more counterweights and sliding them towards the body of the mounting. This may help where the weight limits of a mounting are reached. Particularly with long and heavy refractors. Hanging fewer weights on the very end of the axis shaft may be a poorer choice. Unless you really want to save weight with a mobile set-up.

 

  ~*~

5.08.2024 Oh No! He's at it again!

 ~*~

  9.30 I have been back outside looking at the sun through my Lunt LS60MT.  I am using an old black T-shirt over my head. To shield my eyes from stray light. This really helps to show fine, surface detail and proms.

 I keep wondering about having a fixed pier. Which is a very good idea for imaging. No setup time or polar alignment. Point the telescope lens down and remove the long filtration stack. Now it is far more compact for storage when not in use. A weatherproof box need no longer be as huge as a domed observatory. A simple "sentry box" is all that is required. 

 Another infra red image. Showing a cool hedge after many hours in the sun. Cool grass in the foreground. Warmer weeds near the ground. Odd? Warmer gravel. The green rectangle surrounds a roll of foam backed aluminium foil. It is cool except where it reflects the sun directly to the camera. A good result. Some solar imagers wrap their piers and mountings in this material. To avoid heat build up spoiling local seeing conditions. Convection currents from hot objects could rise through the light path. Causing movement and distortion in the image.

 Is the expense of a domed observatory really such a good investment? The cost is absolutely horrendous! The alternatives not very ideal. The dome provides maximum shelter from the sun and the wind. Further improved with shutters over the observation slit. Above and below the telescope objective.

A roll-off roof building offers only very limited protection from the sun. Only then if the imager sits in the shade of the front wall. There is much less shelter from the wind when the roof is wide open. 

 A new idea: I already have a large building for personal shelter. In the form of the lean-to greenhouse. If  the telescope is pier mounted outside and driven. Then I do not need to be physically close for adjustment. Electric focusing is already arranged. Just needs power.

  I could sit behind the telescope in the greenhouse. Where I could watch the telescope and have my computer monitor and desk. The greenhouse is more comfortable than any open observatory. I can provide solar shade in the form of the nets I already use. I have the mesh covered secondary doors open when it is warm. Providing a comfortable, through draught when there is a breeze.

 This still leaves me with the problem of protecting the telescope from the wind. Removable panels could be arranged on either side, as appropriate, at hedge height. Cloth slows the wind but is not like a solid wing. Too fussy?

 Or, I could have a secure, roll off building. Or roll-off roof. Both of which can be moved to the west as needed. How to maximize wind protection from such a structure? I'll have to think about this. A housing which only needs to look out from east to west via the south. 180º maximum.

 Here we go again: The Calf-O-Tel Plus. A white, fibreglass, roll-off observatory? About £450 equivalent. 😀

• Længde: 196 cm
• Bredde: 115 cm
• Højde: 128 cm

 Stand it on its open end and add some rails for mobility and security against the wind. Add a secure door to what was the open base. What more could you want? A bigger one? This would make more sense:

The CalfOTel Comfort:

• Længde: 200 cm
• Bredde: 120 cm
• Højde: 140 cm

This  one is big enough to house the telescope when parked E-W. About £650 equivalent. The threshold would prohibit rolling away from the pier. Not sure it is a permanent fixture or only fitted for movement. Wouldn't the calves would trip over it if it were always there?

  The XL2:  is designed for two calve and provides greater width. The XL2 is a bit overkill for a roll-off shelter. It is almost observatory sized but without an observation slot.

 The narrower hutches are more attractive as roll-off secure shelters. Their limited height demands off the ground supporting structure and rails. They would NOT reduce the wind buffeting the telescope[s] in use.

 I have emailed CalfOTel in the Netherlands for unit weights. The larger Comfort and smaller Plus hutches each weigh about 35kg. YouTube videos show single persons lifting these smaller hutches manually. Even when fitted with steel work. Certainly doable within the limited space of the front garden.

 

  ~*~

4.08.2024 I don't believe it! H-a observing?

 ~*~

  Sunday 4th. I can hardly believe it! Early thunder and rain, then brief sunshine. Now there was the threat of a very large sunspot. 

 This drove me to collect the various bits of my Lunt LS60MT together into a useful bundle. The H-alpha parts had been greatly extended and attached to the 6" up in the observatory. So had become separated from the objective and its stubby main tube. Once assembled indoors I plopped it onto the Manfrotto tripod,. Then dragged it outside and waited. And waited. Heavy clouds blocked most of the sky.  

 Finally, I had my first view of the H-alpha sun in a very long time.  

 12.00 I upped the power progressively. Until a no-name, 10mm Plossl provided a nicely crisp image at a nominal 45x. I added a TS 1.25" star diagonal for lots more comfort. The sun was high in the SE and my neck had been complaining. No matter how I adjusted the tripod up and down. 

 The multiple splodges of the scattered sunspots were clearly visible. The large spot, coming around the advancing limb, seemed less dramatic. Now it had cleared the limb. Meanwhile, blue holes had steadily increased in the heavy cloud cover.

 12.40 Brief sunny periods at the moment. The afternoon forecast looks much more promising. I'll have lunch and then go back out again.

 14.00 Heavy overcast! All afternoon!

 Sitting on a patio chair on the open lawn and viewing the sun reminded me of two things. There is "dome seeing." From the observatory heating up in the sunshine and causing thermal currents in the air. There is also dome shelter. Which protects the observer/imager from direct sunlight and the wind. And rain of course. Though the latter usually results in closing the shutter(s.) Taking only a few moments compared with rushing indoors with armfuls of equipment. 

 This is the most telling reason for having an observatory. There are others of course. No need for polar alignment providing one has a permanent pier and an equatorial mounting with a memory. Starting up and switching off afterwards should be reduced to a minor irritation. Instead of a complete workout.

 Reading back though my past blog posts. Confirms that I really struggled with highly variable seeing conditions. The plywood dome cladding was certainly a great, solar heat absorber. I had tried draping white tarpaulins. To block the sun. Though with only very limited success. 

 This infra red image is from the other day in bright sunshine. The cool contrast of the vegetation. Compared to the bare plywood of my observatory and shed is truly remarkable. Even the sparse grass in the foreground keeps the ground cool. 

 Just beyond this is the bare gravel. Which is much warmer. Locating a solar observatory looking out over grass makes obvious sense. In reducing local convection currents in the long light path from the sun.  

 Note how cool is the shiny, aluminium tripod ladder. Suggesting a shiny aluminium dome would be much cooler than a plywood one. I shall have to find some white GRP somewhere to photograph with the infra red camera.

[Image from my One+ phone fitted with a USB-C, plug-in, Topdon TC001 infra red camera attachment.]

 Larger apertures are increasingly susceptible to poor seeing conditions. No doubt white paint would have helped. At that time I was against painting the observatory white. It stood out like a sore thumb from the distant road. I didn't want to attract attention.

 A dome is fairly good at protecting large telescopes from the wind. Depending heavily on the wind's direction and the position of the sun in the sky. There were many times I had to dress warmly to cope with a whirlwind in the dome. Despite my massive mounting the telescopes still shook in the wind. Mostly due to end float on the flimsy and badly designed, commercial worm housings. 

 Forum members have expressed doubts. About the wind resistance of the Ioptron CEM120 mounting. This has spring loaded worms but only 216mm [8.5"] worm-wheels. The CEM120 can certainly carry heavy weights. Though its exact design details. Might limit its use in very exposed circumstances. 

 If I should decide to invest in this mounting I should seriously consider its protection in use. I cannot see it performing well out in the open. My front garden is subject to the SW prevailing wind. The raised observatory was rather more fortunate. Due to the shelter provided by all the trees to the west and southwest. The front garden is unprotected beyond the head high, beech hedge. Plus the shrubs I have allowed to grow almost out of control. Mainly to provide interest through the kitchen window and to shelter the greenhouse.

 

  ~*~

3.08.2024 Will the real Pulsar dome please stand up?

 ~*~

  Saturday 3rd. The very high cost of owning a Pulsar observatory made me wonder. Whether I could improve my present but very leaky 3m dome. The plywood surface badly needs to be sealed. Particularly at the joints.

 I could have the local crane hire lift the dome down onto blocks. Where I could safely fibreglass over the plywood. This would add even more weight. Though I would able to work on the shutters from the safety of the ground. They need attention after years of exposure to the weather. Access is presently difficult, dangerous and very exposed. While the dome is in situ on top of the two storey building. 

Once I have the dome waterproof and cosmetically acceptable again. It could be lifted onto a square building in the front garden. Fiberglass layup is a smelly, expensive and time consuming pastime. The resulting dome would be rough on the exterior from the chopped strand mat. Sanding would not improve the surface finish by much. GRP dust is horrible stuff! Itchy and probably dangerous to inhale. A really nasty job. 

 One option would be to buy aluminium sheet. To replace the warped plywood covering panels. This would require very careful bending to match the geometric forms. None of which are exactly the same size! One might as well build an aluminium dome from scratch.

Then there is the "Todmorden" barrel dome. A sort of rotating Nissen hut with sliding sections. To provide the opening [observation slit] for the telescope to see out. This has the advantage of providing lots of room for the telescopes to swing inside the "shoulders" of the protective structure. It can be built of aluminium or [probably] plywood. Having so few joints, compared to a hemispherical dome, should make it more waterproof. A simple lap joint at the roof overlap will prevent rain from running straight inside. There are numerous illustration of their barrel domes on their website.

 https://www.astronomycentre.org.uk/

 Another alternative is to buy just the Pulsar dome on its rotation, base ring. This would be lifted onto a square, timber and plywood box building in the front garden. Saving about £1370 [equivalent] over the purchase of the full height, Pulsar observatory with walls. I'd have to do some checking to get an exact figure. The freight charges might be a bit lower too. 

 The dome-only option from Pulsar. They have some considerable confusion over their dome illustrations online. This is probably the 2.2m. There are too few rotation roller brackets visible for it to be a 2.7m. The usual drop down flap, at the bottom of the observation slit, is missing. Perhaps suggesting a Mk2 dome? 

Who knows? Pulsar doesn't seem to. Most of the international website sales illustrations are for the earlier domes. So anyone ordering one without doing some homework will be very surprised at what eventually turns up! Even Pulsar themselves are showing the two sizes on the same page on their website!

 I have loads of materials to build the walls for a square box base. No additional equipment bay would be required. Since a square box provides lots of extra space in the corners compared to a plain cylinder. A dome-only purchase might need only one [very expensive] pallet. I would have to inquire of the European dealer. 

 There are always cons: A square, box room base would fill the front garden far more than a cylinder. It would also block the light to at least one living room window and to the greenhouse. Squeezing between the building and the greenhouse would be far more difficult than walking past a smooth cylinder too. The grooved plywood I use for cladding is too stiff to follow a curve. Though it might be made to do so with tensioned, ratchet straps.

 

  ~*~

1st August 2024 Pulsar 2.7m observatory pricing. [August 2024]

 ~*~

  Thursday 1st.

 I heard from a European astro dealer giving a delivery charge to central Denmark for a complete Pulsar 2.7m observatory:

Delivery charge €1035 + VAT = €1294 = 9700DKK = £1097. This is just for delivery by freight forwarding. 

The observatory alone would cost 61200DKr  = €81200 = £6923. [£5295 in the UK]

The equipment/accessory bay adds 4850DKr = €650 = £549.  [UK £449]

So dome, including walls and bay = 66050DKr = €8850 = £7473. [UK £ 5744] 

Total incl. delivery = 75750DKr = €10150 = £8570. The difference between UK prices and Danish is probably due to import & VAT charges.  Denmark's VAT is 25%. German VAT is currently 19%. After Brexit there are import charges for UK made items to the EU. 

 Though I thought I remembered that those buying outside the UK need not pay UK VAT. The VAT and import charges are payable in the country of the purchaser. The huge differences here suggest double VAT payment. Perhaps it is the markup by the EU dealers.

The [UK prices in brackets] do not include delivery. Which will vary with location.    

I was quoted 6-8 weeks for delivery.

~*~

30.07.2024 Observatory rambling.

 ~*~

  Tuesday 30th. Another warm sunny day. 73F/23C at lunch time.

 I spent well over an hour, this morning, moving the timber standing against the shed. Over to the back of the newly leveled gravel, parking area. Where is now stacked fairly neatly, but horizontally. This will allow easier access to the observatory for dismantling. I have decided to take down the original, octagonal observatory. It is just an eyesore and won't be used again. 

 The cost of a Pulsar 2.7m replacement escalates rapidly with international delivery charges. I wish I knew if freight forwarding meant delivery to my front door. Having it delivered 200m away on the verge would be daylight robbery! I don't own a powered fork lift truck to bring 200kg to my house. Though the 6-8 weeks for delivery would give me plenty of time to organize a base and pier.  The dome and walls need a flat surface to ensure accurate alignment during the build. I could manage that on plywood sheets laid on sand.

 I have been racking my brains for a more manageable but mobile way. Of mounting the 6" solar telescope at 3000mm equivalent focal length for high-res imaging. One, not involving a fixed observatory. I found this YouTube tutorial posted on my own blog from 2019 but had completely forgotten about it until now. Instead of permanent pier in an observatory it is possible to polar align using the sun itself using SharpCap. I spent many happy hours fine tuning my polar alignment that way.

I'll post it as a link rather than embedding it. Otherwise the fascist despots at YouTube will show random videos on my blog. Once the initial video is watched.

https://youtu.be/zRT-HsRsftI?si=FKGOJ1Spmq-pIpAn

 To get back to the point: A stable four wheeled trolley could be moved down the drive. Complete with a heavy mounting and telescope aboard. To avoid the overshadowing trees and my own house. Roughly aligned using markers. Then fine aligned for imaging using SharpCap. The trolley would need stabilizers once it was parked. Easily managed using caravan and trailer accessories. After use, the whole contraption can be returned to a secure housing. 

 Such an idea would offer no shelter from the sun for the observer. One other major advantage of a dome is being able to avoid direct sunlight. No doubt a sun screen could be devised. Though at the risk of causing vibration from the wind if attached to the trolley. Power would be required. Easily managed with an extension cord.

 A much better alternative: An area in the front of the greenhouse could be cleared. To allow a secure telescope shelter to be moved aside. To expose the telescope already mounted on a fully polar aligned, fixed pier. The H-alpha filtration and camera could be plugged in. After being kept safely indoors. 

 The most important aspect is not having to lift a heavy OTA into place. [Well, not more than once.] The telescope could be turned, nose down beside the pier for compact storage. The secure shelter could become the imager's "warm room." Shade from the sun and fitted with a computer monitor. With a desk for the vital keyboard and mouse. 

 The shelter would be sized to suit the needs of both imager and the instrument. I have loads of 7" industrial rollers. To let the shelter run effortlessly in channel section rails. More timber and plywood than I will ever need for such projects. Failing that I could make a run-off roof. Though I am not very keen on these. Because they leave the imager so exposed. Greater length of the building would allow for a shelter at one end. Leaving the rolling roof safely over "the office." With some sort of closure devised between the telescope and warm room if needed. 

 Blocking the sunlight from reaching the computer monitor is vital. Even in the dome I used to wear black clothing. To avoid my reflection in the screen. This despite the AOC monitor having a low reflection surface. I kept the laptop closed on the desk. Using it for its rapid storage capacity and telescope/mounting control. The latest idea is to use a dedicated mini-computer fixed to the pier. Rather than using a laptop. I wonder what sort of storage these have? An imaging session with a fast camera can easily fill a 1TB SSD.

 

  ~*~

29.07.2024 The clearance.

 

 ~*~

 There is still work to do in dismantling the outer structure at the rear of the observatory. No room for Japanese stepladders between the trees. The two stretch, builder's ladder feels a bit unsafe at that height. The ground is a meter lower at the back. I could work from inside the old observatory if I took down the plywood cladding. Saw the posts off at the bottom first. Then at the top. Saving the wood is a low priority in relation to my own safety. Nobody would find me for ages if I fell. Except by chance. 

 It might be wise to clear all the timber out of the way. A lot of it has been standing up, leaning against the shed for several years and looks awful. In truth it ALL looks absolutely awful! Beauty may be in the eye of the beholder but precious few. Would ever want my 2-storey observatory "decorating" their garden! 

 It will be twice as much work taking down the original and its plywood dome. I am very tempted to remove the cladding. Saw through all the posts at the base. Then just pull the carcass over with the car and a long rope. 

 There are literally hundreds of screws holding the dome together. It would mean dangling from a tall stepladder to undo them all from the inside. I could more easily and safely[?] saw the remains into pieces from the ground. Think of all that free firewood kindling. Or not! The back garden and parking space would become inaccessible. Until the whole job was finished. With the severe risk of countless, sharp, wood screws dropping into the grass. Right where I maneuver and park.

 In case you were wondering: I might have put a Pulsar dome up there. To replace the plywood one. Pulsar very helpfully provide a dome only option. On a tall collar. Which provides the weather seal and a firm rotation base unit in one. However, as mentioned several times here, it would not remove the trees. Nor move the house from the southern boundary. 

 Nor remove the steep, internal stepladder. Needed to reach the observatory floor. Leaving a large, open rectangular, hole in the floor on the western side of the pier. With increasing age it becomes more difficult to climb with a heavy laptop. The laptop must be kept inboard to avoid toppling backward! The risk of falling down the stepladder will increase with each visit. 

 Out of an abundance of care, for my own survival, I want to get back down onto firm ground. There is just enough  space in front of the lean-to green house. On the south side of the house. Even enough room for a path between them. Helped by the curved nature of the intended new observatory walls. The pinch point would actually be quite short. 

By sheer luck there is plenty of shelter from westerly winds. The beech front hedge will hide the walls but not the dome. My neighbours' paddock hedge runs along the side of my drive. Which would place it stretching off for nearly a hundred meters just to the left in front of the observatory. Hiding most of it from the drive and distant road. Without blocking the sky. 

 It all sounds lovely until I have to build a floor and a pier for the new building. I am currently waiting to hear the delivery charge for the observatory. I balked at this last time. Finding that I could have a dome of twice the size delivered all the way from Italy. For less than half the price of a Pulsar. Far cheaper in fact than sending a Pulsar from Germany. Which lies just to the south of Denmark by motorway.   

 16.45 71F/22C. Hot sunshine as I cleared the observatory. I had to dismantle the telescopes to manage the weight down the outside stepladder. Then there was the chest of drawers full of accessories. Brought down one drawer at a time. Still lots more to do. It was very depressing going up there again. Everything was dusty and the massive, aluminium mounting was heavily spotted with corrosion. A period of my life now at an end. After several years of construction, new ideas, modification and endless optimism. Halcyon days. I thought they would last forever. A cup of tea and a rest and then I'll go back to it.

 The equipment is now all safely indoors. For how long? Before it can be brought back into use? Do I have options? Which don't include a whole new observatory?

 

  ~*~

28.07.2024 Demolition continues apace.

 ~*~

  Sunday 28th 64F/18C. Bright sunshine. 

 10.00 Stopped for a rest and morning coffee. I have spent an hour bringing down more of the outer observatory structure. Cutting through the bases of the uprights has sped things up. Though not as much as I would have liked. There are still far too many hidden screws. 

 I also have to be very careful to avoid falling objects. Including myself, now that the outer timber-work is no longer providing security. In the form of a sturdy guard rail. It feels increasingly exposed. Working up at the veranda/observatory floor level. About 9' or 3m meters above the new gravel. With more rubble available but the builders have vanished. For several weeks now.

 I am grateful for the safety of the Japanese tripod stepladder and its very wide base. It's large, metal feet are sticking firmly into the gravel as intended. The ground was originally 3' below its present level. Before I brought in the builder's rubble and topped it off with self stabilizing gravel. 

 12.00 69F/21C. I am dripping with sweat and need another rest! 3/4 of the larger structure has been brought down. Sawing through the bases of the twinned uprights has been the major factor. I had foolishly hidden many of the screws holding the frames together. When I added all the cross braces. 

 Fortunately the joists I used for supporting the observatory floor and cantilevered veranda are still present. Though access grows progressively more difficult now. With the two, nested, buildings overlapping at the side of the shed/workshop. I actually worked from a roof ladder on the shed roof at one point. There was no other way to reach the plywood cladding on that side. 

 I pressed on in the hot and sunny afternoon at 70F/21C. Reaching the screws in that area required a different ladder. I would have had to waste an hour tidying up. To be able to use the Japanese tripod stepladder. It has such a wide stance at the bottom.

 Finally I had removed the last visible screw. So I could drag the uprights free. There is still the junction between old and new observatories to tidy up. I had moved the double doors. To the gap between the buildings for more shelter from the prevailing SW wind. So I built a sort of canopy over it. That all has to come down.  Much of the timber I have removed has long screws sticking out of it. So there is quite a lot of work to do before it can be safely stacked.  

 It is rather sad to be undoing everything I built. Just making it up as I went along. With the advice of astro forum members with more woodworking experience than myself. Apart from the dome leaking it has served me well. With little sign of deterioration or unwanted movement.  

 Who else would be daft enough to choose an octagonal building with a veranda and a trapezoid dome? All the extra wok required to be able to lift components and work safely at such a height. Always working alone. 

 I spent countless hours up there. Imaging the sun in H-alpha. Or occasionally trying my luck on the moon. The overall cost was far more than I had dared to imagine. Though this can be safely divided by the number of hours of use. Not to mention the pleasure of building it. Then finding ways to maximize its performance and ease of use. The chain and crank drive to the dome's roller drive was fun and effortless in use from my imaging chair.

 It kept me at home instead of wandering the countryside on my touring trike. So that was much better for my wife. Who feared I would have an accident one day and leave her all alone. Suddenly I was always around. Or within easy reach. To help with any lifting, mending or chores. The irony is that she went first. Leaving me alone after 55 years of marriage.

 Only now, after two years of apathy, am I finally recovering some of my lifetime passion for astronomy. If not now, then when? I am 77 and have just had an operation to open up my clogged heart arteries. Who knows how many years [?] I have left of physical and mental fitness? To be able do anything of real interest for myself. 

 I am dismantling the observatory to provide the materials to start anew. Not from on high in the wooded back garden. But in the narrow front garden. Where once the sun never shone. Was never allowed to shine.

 The final picture shows the progress today after tidying up the debris.

  ~*~

26.07.2024 First frame brought down.

  ~*~

   Friday 26th. After a wet day the sun came out. I managed to get one frame down from the observatory. It will be mostly dry for the next two days. So I can continue the search for the 150mm/6" screws holding the frames together. It feels rather unsafe standing up there now. With only the few remaining boards left over from the original veranda. With nothing outboard. The frames and noggings provided a sturdy handrail.

 I had a sudden inspiration for a new pier. If I am to invest in a Ioptron CEM120 mount. The old pier from the Fullerscopes MkIV is still standing in the garden. I welded it together at work many years ago. The original "smelly" Hammerite paint has protected it quite well.

 The high hedges drove me to invest in trailer guide wheels for a little mobility. Not helped by the top heavy nature of the contraption. While the uneven ground made it very unsafe. Particularly with a 7" f/12 refractor aboard!

 I could lose the wheels and use the sturdy tubular feet. To provide underfloor leveling via 16mm studs. [Screwed rods.] Failing that I can cut off the legs and pour concrete around the 7" thick wall pipe. It has a strongly welded top plate. Which can be adapted to the CEM120 base plate. 

 I'll make an intermediary adapter, with suitable bolt spacing, from thick aluminium plate. Commercial adapter plates cost a king's ransom! As do the simplest pretensions of a telescope pier. Most of which are far too low, as standard, for a refractor. A thousand quid just to hold up a mounting? £1500 for a heavy, tripod-pier? Which isn't even mobile without crane hire! Ridiculous! They are just playing to the vanity of wealthy amateurs.  

I am doing it all wrong! There is no need to drop the frames as units. Just because that was how I raised them. I can use a bayonet saw to sever the uprights near the ground. Just above the steel work will do. Then I climb up to the veranda level and cut through the cross pieces. Drop the uprights as single units. That way I don't have to search for the screws. The uprights are no less useful for being only slightly shorter.

  ~*~

 

25.07.2024 Demolition continues!

 ~*~

  Thursday 25th. Warm and sunny. I spent most of the day dismantling the outer observatory building. I had to remove more of the plywood cladding. This took some time because of the poor ladder access through the trees growing close behind the building. 

 First I had to remove all the plywood leaning against the building. I just laid it in a stack on the ground. It was already wet from all the rain while standing on edge.

 Then it was a matter of removing umpteen 6" screws. Which were holding the vertical frames together. I had rather foolishly hidden many of these screws with the 50x100mm noggings. The horizontal timber braces. 

 No matter how many screws I removed there were always more. So that the frames refused to be pulled over with a long rope. 

 The image shows the result of today's activity. Most of the horizontal timbers have gone. I had deliberately made the larger building separate from the original, inner one. It is just a matter of searching out the last of the screws. They are all driven just under the surface so are difficult to spot.

 The DeWalt screwdriver is noisy but excellent for this job. Having enough torque to undo even a 6"/150mm Torx screw. Without viciously twisting my hands and wrists as the electric drill had done. When I was inserting the screws. I need to dismantle the observatory to reclaim all the concrete carport anchors. With which I supported the timber uprights. On both the later and older buildings. 

 The shrub growing wildly in the foreground was supposed to have disappeared. When I started spreading gravel to level the area. I had cut it right down but it has come back with a vengeance!  It produced pretty flowers when it half hid the observatory. It had been there for 28 years.

 

 

  ~*~

24.07.2024 Update on solar options.

 ~*~

  I have made a good recovery from my "surgery by wire." Having ridden over 200km on my bike in the last week alone. A series of hospital appointments suggest I may yet live a bit longer.

 I have continued to monitor the solar astronomy, imaging forums. My interest is rebuilding itself steadily. 

 There are several serious hurdles to overcome. The larger observatory is only half demolished. That was put on hold while I had my health issues fixed. The original 10' [3m] observatory still stands within the shell of the larger building. Sadly the plywood dome continues to leak like a sieve. Access at such a height is far too dangerous to apply any external remedy. Which severely limits the use of the observatory. 

 The wisest way forward would be to totally demolish the entire observatory. It is an eyesore and difficult to believe it will ever improve. Placing an observatory on the ground in the same spot would be utterly pointless. The surrounding trees and hedges are growing wildly.

 I have a tentative plan to erect an observatory in the front garden. This would house my 150mm/6" H-alpha solar refractor. Which will be supported on a heavy duty equatorial mounting. Probably an Ioptron CEM120. My first ever purchase of a commercial mounting! I think I have waited long enough at 77 years of age and counting. 

 The sky from the proposed site is blocked by trees to the west and east. Though I would still get many hours of completely unimpeded sunshine to play with. Just no early or late sun. Which only sometimes raised the hope of better seeing conditions. Fields stretch for miles to my south. With only a few houses dotted at various distances. The nearest a low farmhouse at 65metres to the SSW. This is hardly likely to noticeably affect my seeing conditions.

 The observatory needs to be guaranteed to be simple and easy to use. The boundary beech hedge will be quite close but can be trimmed to match the lowest altitude. At which the sun is ever likely to be visible in winter. 

 I really like domes but have no plans to re-use my preset dome. It needs far too much work to become pretty and [far more importantly] waterproof. Do I want to spring for a 2.7m Pulsar dome? I am not sure. It is a lot of money but provides a turnkey solution without much compromise. It is no smaller than my present dome. Once the plywood ribs and base ring are taken into account. The Pulsar is relatively clean of projections internally. It would require no maintenance over the likely time I have left. It can also be sold relatively easily by those I leave behind.      

 It would need a concrete slab to be stable in the SW gales. The pier is an issue. I have loads of seamless steel tubing in all sizes to be used as a former for a concrete pier. This would need a suitable bolt arrangement at the top. To level and fix the mounting securely. An internal plastic pipe can allow easy, internal pier cabling.

 

  ~*~

18.06.2024 Whoops!

 ~*~

June 18th Update.

 An angiogram triggered a need for emergency surgery. I proved to have two blocked arteries feeding my heart. After suffering horrible pain the following night I was rushed to hospital for surgery. This was a few days ago now and I am now convalescing. I could barely cross the room without becoming breathless on my return home. It will obviously take some time before I can return to demolition duties.

 

  ~*~

14.04.2024 Observatory dismantling Pt.1.

 ~*~

 Sunday 14th. 52F/11C. Sunny, dry and breezy. First I leveled the new gravel area beside the observatory. This was so I could safely set up the stepladders on firm ground. 

 Then I started to dismantle the observatory. Removing the cladding plywood was simple enough. The original building had retained its cladding. Until I was ready to carry out the internal changes to suit the big, green dome. [Now sold and gone.]

 The enlarged building, floor plan, was offset and larger in nominal diameter than the original octagon. By 1.3meters towards the west.  

 Once I clear all of the external skeleton I will make a decision on keeping the 3m/10' observatory building. It doesn't loom nearly so large as the expanded building.

 Now I must do a lot of tidying of the timber which I had stored in the green dome. Though a rest is required first to recover from this morning's exertions.

 The timber was tidied up and a couple more panels were safely dropped. I invested in the tall stepladders for safety reasons. After having several falls as normal ladders slid sideways. Or sank into the ground with the same effect. I suppose I am lucky to be alive. 

 These tripod stepladders are incredibly strong, stiff and stable. With double rungs for long term comfort and safety while working from them. They have large metal feet, yards apart. Which don't sink or slide.

  16.45 A new image added. I have removed a lot of cross braces. They were skew screwed with 100mm Torx. It is a great advantage to a have a proper rechargeable screwdriver with torque settings. Electric drills don't have the power. Unless set to Drill mode. Then they tear your wrists and hands as the drill body rotates. As it finally drives the screw home.

 I have had enough for one day. The next step is to unscrew the lower cross braces from the projecting floor joists. Then the large, coach bolts can be undone at the top and each frame separated from the skeleton. This was the only way I could erect the building safely while working alone.  

25.04.2024 Update: All work came to a complete halt due to a severe cold.   

  ~*~

 

13.04.2024 Ever onwards?

 ~*~

  Saturday 13th. I have had several trailer loads of free demolition rubble delivered. To make up the sunken ground level beside my 2-storey observatory. 

 I still have to spread the self compacting gravel over the top. To make the surface firm and level. Then I can safely erect ladders to start dismantling the observatory. 

 To be replaced by a self-built car port. Probably using much of the observatory timbers and grooved cladding plywood for materials. 

 My health is under serious review. With numerous scans to examine my heart and its plumbing. I become very breathless with any physical exertion. Which is certainly not conducive to my projects!

 I still have no clue what to do with my collection of optics. My self-built telescopes will not support the used price structure of well known makers. Though the 6" and 7" iStar objectives and larger FT focusers do have some value. My massive equatorial mounting would be viewed as scrap. By all but the most knowledgeable amateur astronomer.

 I am still tempted to build a simple, compact, roll off roof observatory in the front garden. To give me some rather limited, southerly views of the sun. There would be no need for a raised building to see over the hedges and trees. As was vitally necessary for my back garden viewing. 

 An earlier view before the rubble was spread in the sunken area beyond. I had used up half the gravel heap at this point. To make up the lower ground.

 Solar H-alpha imaging still holds some interest. If only I can re-motivate myself to start all over again. The new, southerly arc would be much narrower than I enjoyed from my former eyrie. Early and late seeing conditions were usually best. At least I wouldn't be viewing the sun over the hot house roof. There is only a modest field in front of my southern boundary.

 Some sort of secure, weatherproof covering would be necessary. To avoid repeatedly lifting instruments into place. I no longer have that capacity. My plywood dome allowed me to use a block and tackle to lift my OTAs as necessary. Mounting my 6" F/10 H-alpha scope would have to be strictly a one-off effort. I couldn't do it every time I wanted to do any solar imaging. I am only interested in solar close-ups.

Two more meters of backward progress spreading the gravel. It is very hard work! The gravel is hard to penetrate in the heap and heavy to throw over three  meters with a shovel. So I resorted to using a wheelbarrow. Even more tiring but much quicker.

 I used opposed ladders. To form a sturdy A-frame for a chain hoist. When I needed to lift my foolishly heavy mounting onto its 14' pyramidal pier. I don't know of any budget, commercial, equatorial mountings with remotely the capacity to support a heavy, 6" refractor. 

 There is always the option of a Dobsonian fork mounting placed on top of an equatorial platform. That would give me the tracking I need. Without image rotation. I don't need whole sky coverage for solar. 

Last picture for today. I have now covered an area 8m x 4m with gravel beyond the steel post. 26'x13'.

 If my health deteriorates further I shall just have to give up all of my foolish plans. 77 isn't a bad innings I suppose.. Though I had no plans to retire from continuing with my projects. And then, my wife died suddenly and all my hobbies became completely meaningless.

 

  ~*~