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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.
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.
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