How close can you get to buildings?

[rfdesigner]

I'm thinking obsy here.

After many problems, we should be into a new house within a month.

The only house in line with the southern horizon will our own, which I'm intending on insulating very well, so no major issues. Beyond that there isn't another building for maybe half a mile or more, and then it's only the odd one or two. (SSI, then National Park). We'll be just north of the SSI.

It occured to me that maybe there's a minimum distance to buildings before they have any impact on the seeing.

Anyone have any experience?

Derek

[Catanonia]

A good 15 foot or more and I have no issues with our house brickwork getting very warm during the day and radiating away during the night. Watch out for heater vents though, they are a killer to your images.

[rfdesigner]

Thanks

I should perhaps have mentioned I'm thinking here of distances touching on 100ft. There is a vent from the Aga which will be going 24/7 (unless it runs out of oil) so at what distance will that no longer be a problem?

[barkis]

As far as proximity, the main problem is usually from heat sources.

Any heated building, such as a house, or workshop/factory, means heat will dissipate through the roofs, and disturb any incoming rays from the sky if the pass through the disturbance.

Our local observatory overlooked a local Technical College, and it badly affected seeing with the 16" f6 Newt.. The roof of the building was about 25 metres away. There was a lack of foresight in placing the observatory in the position it occupies.

Ron.

[Nosivad]

I would have thought that 100 feet ie approx 30m, would be far enough from you so that heat radiation or convection should be fairly insignificant. If a house is 8m high, at that distance of 30m the top of the roof is at an elevation of about 15 degrees, so it might get in the way of some very low objects but the atmosphere would be very disturbed at that level anyway.

[rfdesigner]

I would have thought that 100 feet ie approx 30m, would be far enough from you so that heat radiation or convection should be fairly insignificant. If a house is 8m high, at that distance of 30m the top of the roof is at an elevation of about 15 degrees, so it might get in the way of some very low objects but the atmosphere would be very disturbed at that level anyway.

The ground slopes towards the house, so the obsy is maybe a whole story higher than it would be on the flat, so the view isn't really impacted.

I am looking forward to the purchase of a chainsaw though

Derek

[pete_l]

I should perhaps have mentioned I'm thinking here of distances touching on 100ft. There is a vent from the Aga which will be going 24/7 (unless it runs out of oil) so at what distance will that no longer be a problem?

I doubt if the Aga would be a concern.

In practice you wouldn't be observing at low angles, as the amount of air between you and your target is considerably greater at low altitudes - and therefore contributes a lot to turbulence and extinction (light absorbed by the atmosphere).

[Nosivad]

.

I am looking forward to the purchase of a chainsaw though

Derek

I've got one you can borrow

[rfdesigner]

I doubt if the Aga would be a concern.

In practice you wouldn't be observing at low angles, as the amount of air between you and your target is considerably greater at low altitudes - and therefore contributes a lot to turbulence and extinction (light absorbed by the atmosphere).

True 99% of the time.. but there is no other way to image objects at -20 degrees declination.

In fact the way the site is, the lowest horizon is due south. There are loads of trees, most of which will be my responsibility.

(oh shucks.. house has no central heating and relys on an excellent wood burning fire + aga.. so I'll need all the fire wood I can get .. Just hope I can find a source to keep us warm until the fresh stuff is dried out)

Oh yes... no TPOs either.

[Catanonia]

I would ay as you describe the location, you won't have a problem.