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    Re: Position from solar eclipse photo
    From: Greg Rudzinski
    Date: 2013 Nov 19, 14:23 -0800


    Hs was estimated by eye using the Sun diameter as a reference and guessing at the horizon. Time and height of eye are also round estimates to get an intercept to pass through the known position. I did not use celestial other than Sun azimuth to find the photographer. Getting the same spot as Don using the Empire State Building width compared to the horizontal Sun diameter was perhaps lucky by +/- a nautical mile.

    Did the lunar get done right ? Limb reference (near /far)is a bit confusing when dealing with an eclipse image.

    Greg Rudzinski

    Re: Position from solar eclipse photo
    From: Frank Reed
    Date: 2013 Nov 19, 13:51 -0800
    Greg Rudzinksi, you wrote:
    "Attached is my plot."

    That's a very impressive plot, Greg. From the appearance of the calculation, it looks like you did it entirely from the astronomical and celestial navigation data. But what do you think? Is your fix astronomical? Also, what's the sensitivity? For example, you got the time by treating the eclipse as a lunar distance observation. Even I, "Lord of the Lunars" (I have just crowned myself), did not use that. How accurate is the UT derived from that. I tried a couple of different ways to estimate the time and could not fix it better than a minute or so by purely astronomical means. But now that we have the exact location (based on overlap between foreground and background objects), we can probably give a rather exact UT for the photo. And I see that you've estimated "Hs" values. I can place lower limits on Hs, of course, but I'm not really sure where the true (or apparent) horizon would be in this photo. How did you estimate that?

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