NavList:

Hewitt:

Iam still "here", likely more than somewhat overwhelmed by the input from helpful professionals such as Frank Reed, Garry, Anabasis and others..

Re sights, I haven't tried averaging, something I likely should as when at the beach, spring and fall, weather allowing, I usually do a run of shots, 5 upper limb of sun, 5 lower limb of sun. I try o allow 5 or 6 hours between shot runs, to get a better spread between LOP's.

I also, when both are available, shoot sun and moon, usually a string of 5 shots each upper and lower limbs, when possible, so I would have sufficient data to average, I believe. As to your observation about "From your posts I have the impression you've started right in on multi-body fixes, and difficult ones at that." I've tended to doing things the hard way for years and years. Fools rush in and so forth. At home, in Pittsburgh, it's a case of shooting across the Monongahela River down town, the distance is 500 or so yards, requiring the dip short correction, and then there are boats going by, or standing in the parking lot at our apartment complex, using an artificial horizon, shooting the sun in AM and again in the PM 5 hours or so later. Using the AH, once I opted to actually read the instructions, my calculated positions are usually quite close to GPS coordinates, within a couple of miles, sometimes less. Shooting sun, as above described, at the beach, I usually end up within a couple of miles (2 to 3) of GPS coordinates, and have come as close as 1 NM. Of course, there were some shots about which the less said, the better. The three body fixes I've done, at the beach were shot at evening civil twilight or thereabouts.

Greg:

On your comments regarding the three body fix I posted, Altair, Fomalhaut and Jupiter, 23 October, the data I posted are, as I recall, what Frank had requested. As for Height of eye, and IC that you questioned, the H/E was 6', IC was 0.1' Off Arc, or so it appeared. My a distances were all Toward, and my "fix" was inside the "cocked hat" or triangle. I determined it's location via an exercise in geometry, didn't think I remembered any, bisecting each side of the triangle, erecting a perpendicular, and extending this line for each side. Where the lines crossed, is the location of my fix, or so I assumed. The time between shot of Fomalhaut and the others, being longish, could have thrown the whole thing off, but I ended up, measuring with dividers, with my fix being less than 2 NM fro GPS coordinates, as mentioned previously. Maybe just dumb luck, I cannot say.

Even with weather permitting, here in Pittsburgh, doing star shots "downtown by the river" is, due to light pollution, an exercise in futility, and beside that, it's often cloudy, not to mention cold this time of the year. I'm limited to using the AH in the parking lot during the daylight hours, weather permitting or delving through a couple of years worth of data derived from standing on the beach in North Carolina.

As I mentioned to Anabasis, being at sea, I never have been so, where one has a 360 degree horizon must be and entirely different situation, for shooting in North Carolina, from my location there, I'm limited to shooting with an arc running from roughly 110 Degrees to 250 Degrees. I plot stars with the 2102-d, but realize that I'm missing one hell of a lot of sky. Shooting to the North is out, as I'd be over the land. Problems, everywhere..

All:

Lest I forget, thanks for your patience, time, attention and efforts.

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