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Dear Roger,
Welcome to the list.

> The first question I have is:  I live on a hill overlooking the ocean
> but dont know my elevation to set the dip.

There are several ways to do it.
1. Ask a friend who has a GPS to measure your altitude. My experience
shows that sometimes GPS gives errors up to 50 meters in altitude,
but usually it is OK.
(In the US, you do not even need a friend with GPS for this.
Just go to the department store, buy one, measure your altitude and then
return the GPS:-)
2. Take several Sun sights.
Take them with real horizon first, then with artificial
horizon. This method is not very precise though; you have to
take many sights and average them. You also have to determine
your index correction very precisely and to choose the time when the
real horizon is very sharp.
3. You say that you have a precise map of your neighborhood.
I suppose that this map does not show elevation of your house,
otherwise the problem would be trivial.
Now it depends on what you really see from your location.
Perhaps you can see some well defined shore line, or a building roof,
or any other horizontal line perpendiculat to the
line of your sight whose location and
distance
you can
determine from the map. Then measure the Sun's altitude against this
line.
4. Everything depends on the circumstances, on what you can really
see. For example, if you can see your house from the shore,
and the hill is really steep, you can try to measure the altitude
of your house roof from the shore using artificial horizon.
5. If you can see the horizon from your location in TWO OPPOSITE
directions, you can try a back sight (with some object in the sky
whose altitude is more than 60d. On your latitude, Sun can be used.
(I really envy your location if it permits you to do this:-)
6. The problem becomes much easier (and the solution more precise)
if you can use any surveying instrument (surveyors level, theodolite)
with a precise bubble level.

Alex.
P.S. If needed, I can supply a formula for each case listed above,
or any other measurement you choose to try.

   

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