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Frederf · 09-26-07, 02:55 PM

Using the big dipper is no good as I was at 3°N and 1°S latitude respectively, the big dipper was through a couple billion tons of rock and slgihtly hard to see. Again this is a small matter that simple practice and star charts can easily remedy, not worried at all.

Actually my SR/SS times came from Almanac 1.0 by Stephen R. Schmitt, 2002 but I checked them across to the tables that came with the mod and seem very close. I'll do a direct comparison (since I inputted a weird lat/long that's not on the table).

20N Mar21 1943
Table: SR 0604, SS 1810
Almanac1.0: SR 0604, SS 1811

30N Jun4 1939
Table: SR 0431, SS 1924
Almanac1.0: SR 0432, SS 1924

So it looks like the table is from the same data (perhaps the same program, pre 1950 being hard to get) and the table simply averages over 1939 to 1945 while the program does not. Another thing I noticed is that setting the time zone to anything other than +0 Z in the settings gives confusing results. It seems to say "The local time in time zone X will be _____ when the sun is rising in time zone Z." which may be right but is entirely unhelpful. The local time that the sun rises in each time zone on any given day of the year should not be more than 10 seconds or so different.

I've also found that the calculated sunrise, the upper limb rise, the center body rise, and the red light switch happen at 4 seperate times. This notion of "The red light goes off when the sun is half way out of the water" doesn't hold true in my experience. Instead the red light tends to go off a few minutes after half-sun.

More testing ist reqwuiret.

09-26-07, 02:55 PM	#27
Frederf Seasoned Skipper Join Date: Apr 2005 Posts: 665 Downloads: 79 Uploads: 1	Using the big dipper is no good as I was at 3°N and 1°S latitude respectively, the big dipper was through a couple billion tons of rock and slgihtly hard to see. Again this is a small matter that simple practice and star charts can easily remedy, not worried at all. Actually my SR/SS times came from Almanac 1.0 by Stephen R. Schmitt, 2002 but I checked them across to the tables that came with the mod and seem very close. I'll do a direct comparison (since I inputted a weird lat/long that's not on the table). 20N Mar21 1943 Table: SR 0604, SS 1810 Almanac1.0: SR 0604, SS 1811 30N Jun4 1939 Table: SR 0431, SS 1924 Almanac1.0: SR 0432, SS 1924 So it looks like the table is from the same data (perhaps the same program, pre 1950 being hard to get) and the table simply averages over 1939 to 1945 while the program does not. Another thing I noticed is that setting the time zone to anything other than +0 Z in the settings gives confusing results. It seems to say "The local time in time zone X will be _____ when the sun is rising in time zone Z." which may be right but is entirely unhelpful. The local time that the sun rises in each time zone on any given day of the year should not be more than 10 seconds or so different. I've also found that the calculated sunrise, the upper limb rise, the center body rise, and the red light switch happen at 4 seperate times. This notion of "The red light goes off when the sun is half way out of the water" doesn't hold true in my experience. Instead the red light tends to go off a few minutes after half-sun. More testing ist reqwuiret.