Topography & Seeing

[Constant (David)]

Our house is located on the on a Southern facing wall of an escarpment. Often I can use my WO 3.5mm and enjoy magnificent planetary viewing, ATM the views of Saturn are nothing short of breathtaking in the WO 3.5mm.
My question is..... does the fact that our house is situated on a ridge-plateau and that the house and the ridge obscures light from Sydney and the light from Western Sydney explain our good seeing, is it possible to have localised good-seeing?
I had thought seeing was determined by the collum of atmosphere we gaze through rather than localised topography? I can appreciate its a good thing that we observe under a significant Sydney light-shadow though this in no way excludes us from the massive light dome Sydney produces.
Have other Icers noted the effect of light-shadow? Am I simply confusing some good seeing with what I perceive to be a local shadow-effect? Am I subscribing too much to the effect of being in a shadow?

[casstony]

The shadow only affects the darkness of your viewing site; it won't have any effect on seeing. Air turbulence from the Jetstream or local heat sources and every level in between determine the seeing and magnification you'll be able to use.

I'm envious of your stable skies and good planetary views. I've got a fairly dark yard but very unstable seeing and I'm usually limited to 100x.

[ZeroID (Brent)]

Topography can have some effect locally for sure. I'm close to CBD but a bit higher than average up the slopes of a local volcano ( extinct fortunately ). It gets me a wee bit above the local suburban fug, car fumes, smoke, dust etc by about 30 meters. Doesn't sound like much but also being away from local streetlights a bit it does make a difference to local air clarity.
You don't say how high you are up the escarpment but just the altitude factor can help a bit for sure.

Unfortunately it doesn't fix clouds ...

[Constant (David)]

Originally Posted by casstony

The shadow only affects the darkness of your viewing site; it won't have any effect on seeing. Air turbulence from the Jetstream or local heat sources and every level in between determine the seeing and magnification you'll be able to use.

I'm envious of your stable skies and good planetary views. I've got a fairly dark yard but very unstable seeing and I'm usually limited to 100x.

Given the favourable conditions I really should place a camera in the light path. Intuitively I feel that opportunity has conspired with circumstance to provide what seems to be great seeing, though of course the light dome and atmosphere is there as it always is....

[Constant (David)]

Originally Posted by ZeroID

Topography can have some effect locally for sure. I'm close to CBD but a bit higher than average up the slopes of a local volcano ( extinct fortunately ). It gets me a wee bit above the local suburban fug, car fumes, smoke, dust etc by about 30 meters. Doesn't sound like much but also being away from local streetlights a bit it does make a difference to local air clarity.
You don't say how high you are up the escarpment but just the altitude factor can help a bit for sure.

Unfortunately it doesn't fix clouds ...

We can line of sight see the local trig @ 129m above sea level. It's not that high, but we are on the upward slope heading South as you leave the Sydney basin.
We are also relatively well sheltered from street lights, though in the distant there is a very annoying line of street lights.