Building the Octagon Pt.50 Possible Observatory Roof Forms.

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It is assumed that the observer and their instrument[s] will need protection from the elements. This covers a huge range of options from a simple tarpaulin to a fully enclosing dome with observing slit and shutter. Each conscious step provides increased shelter from wind, cold and rain. By providing walls, but no protective roof, a roll-off roof [ROR] provides more shelter than a roll off observatory. 

My own choice is having as much shelter and enclosure as possible. Denmark is often breezy and cold. So walls [alone] are not [quite] enough for improved observer comfort. Comfort is subjective and both physical and psychological. Just knowing that reasonable shelter is available increases the desire to go out in the dark and cold. Rather than sit and watch Netflix in the warm. This is not a casual choice.

The observatory [if it functions well] provides instant gratification. The owner can dress accordingly, go outside, open the observatory, switch on the drives and laptop and start slewing, observing or imaging. Anything involving heavy manual labour, or jumping through hoops in the dark, means that Netflix remains the comfortable [though lazier] option. 

The cost of building an observatory is not trivial. The cost of watching Netflix is. [Well almost.] So the observatory had better fulfill its intended purpose or the considerable expense is largely wasted. Why even bother if it involves hurdle jumping while blindfolded? Those hurdles may well be both physical and/or psychological. So they must be carefully analyzed and all effort required, prior to beginning observation [or imaging] must be removed from the equation.

It might well be considered obsessive to build an observatory in the first place. It certainly needs justification if it is not just intended as a status symbol. Though whom it might impress is a matter for some debate.

My own excuse is the lack of clear sky requiring a raised observing platform. So far, so good. Now I am up there, I demand some creature comforts. I want my instant gratification, or else. So I don't want to be getting lots of things out of waterproof bags or boxes before I can "get going." Protective shelter is essential for all the kit to function from switch on. 

A platform with walls is only a third of the way there as far as I am concerned. Tarpaulins are always heavy and stiff when cold. They collect rain and snow and always tip their harvest straight onto the observer and/or his kit. So now I demand a roof. One which provides all sky vision without needing an umbrella every time it is opened up. A wide enough slit not to need constant attention as the sky rotates outside would be nice. Something not too heavy to lift or turn is essential.

These demands have been fulfilled in only a very limited number of geometric/material forms over time. Mostly in the way of hemispherical domes. Minimum volume with minimum material consumption in its construction must be weighed against the greater difficulty and/or cost of 3D construction. A dome is traditional and suggests some seriousness is being applied to the hobby. Though not exclusively and I mean absolutely no disrespect. Other shapes are certainly possible and some very expert imagers work "naked" out in their gardens. Or even on their drives, patios, terraces, lawns or decks.

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