Sorry Neal, I never used that method to take LAN ..... too hard to judge
the right moment .... if you're going to use this method, best to take a
sight 10+ minutes prior to LAN and note the time and sextant altitude,
the take LAN (no close time really needed) then a third sight and time
when the sun returns to the altitude of your first sight, and work time
for LAN from that.

otn

That's a good way to do it when the seas are rough and
the horizon hard to judge. We call that extrapolation.

S.Simon


"otnmbrd" wrote in message ink.net...
Sorry Neal, I never used that method to take LAN ..... too hard to judge
the right moment .... if you're going to use this method, best to take a
sight 10+ minutes prior to LAN and note the time and sextant altitude,
the take LAN (no close time really needed) then a third sight and time
when the sun returns to the altitude of your first sight, and work time
for LAN from that.

otn

The higher the sun is a LAN, the more accurate you may get, using your
method. However, the lower the sun at LAN, the less accurate.
It has less to do with rough seas and poor horizons.
Biggest problem with your method is getting an accurate time for LAN.

otn

Simple Simon wrote:
That's a good way to do it when the seas are rough and
the horizon hard to judge. We call that extrapolation.

S.Simon

Does your sextant show the entire disk of the sun in the mirror?

Mine does. There's a fancy name for this trick that I forget
what they call it but it makes it pretty easy to tell when the
Sun stops climbing and starts descending in the heavens.

S.Simon


"otnmbrd" wrote in message ink.net...
The higher the sun is a LAN, the more accurate you may get, using your
method. However, the lower the sun at LAN, the less accurate.
It has less to do with rough seas and poor horizons.
Biggest problem with your method is getting an accurate time for LAN.

otn

Simple Simon wrote:
That's a good way to do it when the seas are rough and
the horizon hard to judge. We call that extrapolation.

S.Simon

ROFL Shame I have to go out tonight. I'll answer you tomorrow Neal.
Gawd, what a frawd.

otn

You don't have a clue as to what I'm saying or talking about, do you?
Of course my sextant shows the entire disc of the sun, but it has
nothing to do with my sextant and everything to do with my latitude in
relation to the declination of the sun.

ton

Simple Simian wrote:
Does your sextant show the entire disk of the sun in the mirror?

Mine does. There's a fancy name for this trick that I forget
what they call it but it makes it pretty easy to tell when the
Sun stops climbing and starts descending in the heavens.

S.Simon


"otnmbrd" wrote in message ink.net...

The higher the sun is a LAN, the more accurate you may get, using your
method. However, the lower the sun at LAN, the less accurate.
It has less to do with rough seas and poor horizons.
Biggest problem with your method is getting an accurate time for LAN.

otn

Simple Simon wrote:

That's a good way to do it when the seas are rough and
the horizon hard to judge. We call that extrapolation.

S.Simon

OTN,

Now, with your explanation, Neal may be able to get a Local Noon sight.
Maybe, I'm still not sure he aware of what we are talking about. Hitting
a high noon fix with the Earth traveling over 900 MPH is kind of like
catching a Fly with Chop Sticks.

OTN your method is the correct way to take a Noon Sight. Even the
instruction that came with Neal's (Also mine) Sextant explains the Noon
Sight that way.

Ole Thom

Actually, I never used this method, except in an "emergency". The
normal method used, was to get a couple/few morning sunlines and do a
running fix by moving them up along the course line and crossing them
with the LAN sight.

otn

Thom Stewart wrote:
OTN,

Now, with your explanation, Neal may be able to get a Local Noon sight.
Maybe, I'm still not sure he aware of what we are talking about. Hitting
a high noon fix with the Earth traveling over 900 MPH is kind of like
catching a Fly with Chop Sticks.

OTN your method is the correct way to take a Noon Sight. Even the
instruction that came with Neal's (Also mine) Sextant explains the Noon
Sight that way.

Ole Thom

Some of the older model sextants used half mirrors instead
of the modern see-through mirrors that make it possible to
have the sextant picture a sunset at LAN. The older
sextants were harder to use.

You being old and retired, I figured you'd probably have
some antique instruments.

S.Simon


"otnmbrd" wrote in message ink.net...

Actually, I never used this method, except in an "emergency". The
normal method used, was to get a couple/few morning sunlines and do a
running fix by moving them up along the course line and crossing them
with the LAN sight.

otn

Thom Stewart wrote:
OTN,

Now, with your explanation, Neal may be able to get a Local Noon sight.
Maybe, I'm still not sure he aware of what we are talking about. Hitting
a high noon fix with the Earth traveling over 900 MPH is kind of like
catching a Fly with Chop Sticks.

OTN your method is the correct way to take a Noon Sight. Even the
instruction that came with Neal's (Also mine) Sextant explains the Noon
Sight that way.

Ole Thom

The horizon glass was a half mirror that was not at all difficult to use.
I'm not sure what you are referring to regarding "picture a sunset at
LAN" if you are talking about the brightness of the sun, shade glasses
took care of that. As for dipping the sight at the time, swinging the
sextant solved that issue.
G My sextant may now be considered an antique, but it's still probably
one of the best instruments built .... still has original mirrors.

otn

Simple Simon wrote:
Some of the older model sextants used half mirrors instead
of the modern see-through mirrors that make it possible to
have the sextant picture a sunset at LAN. The older
sextants were harder to use.

You being old and retired, I figured you'd probably have
some antique instruments.

S.Simon