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Old 01-26-2019, 12:00 PM   #21
Front Runner
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Default Eureka!! Understanding!!

Quote:
Originally Posted by propbeanie View Post
There are no settings in the missions nor in the CareerStart, Flotillas or PatrolObjectives. I also cannot find anything in the cfg folder. You would think there is something somewhere, but I haven't found anything. I'm going to do some Fremantle versus Brisbane starts later this evening, and see what happens with time West of the IDL...
OK, I understand what is going on when using the US Navy Almanac vs the SH4 game world. Looking at this (interactive) World Time Zone map.......

http://www.geoastro.de/astro/astroJS...e/worldmap.htm

(Navy Almanac for reference)
https://aa.usno.navy.mil/data/docs/RS_OneYear.php

......you will notice that both Midway (X) and Pearl Harbor (W) are designated one time zone to the east of their actual, longitudinal, time zones!!
Longitudinally, Midway is actually in the (Y) time zone and Pearl Harbor is actually in the (X) time zone.

So, here we go again..... Midway is longitudinally -12 hours (or 12 hours West of GMT.) Pearl Harbor is longitudinally -11 hours (or 11 hours West of GMT.) This is why the US Navy Almanac works when you use the 11 hours West of GMT variable to verify your sunset time when leaving Pearl.

To determine Sunset time when based at Midway using the US Navy Almanac, you must use the variable 12 hours West of GMT. Even though Midway is listed as being in the 11 hours West of GMT for "official" time keeping purposes. That's why this is so confusing to us SH4 sailors. The SH4 game world is properly simulated longitudinally as far as celestial events are concerned as opposed to the somewhat arbitrary "time zones" assigned by "man".

In fact, when within 7.5 degrees longitude of 180 degrees (East or West of the Prime Meridian), you can use + or - 12 hours and arrive at the same time. For Instance, Fiji is 12 hours East (+12) at 178 degrees east longitude and Midway is 12 hours West (-12) at 177 degrees west. On the Midway side of the line it is today, on the Fiji side of the line, it is tomorrow.

Just remember, when you are based out of Pearl, or Midway, and you travel West of the IDL, your Base time is what time it is at Midway, or Pearl, and the date is yesterday.

I know this has been discussed at length many times before. It has always confused me.

Now I understand the math behind it. The SH4 team made very good decisions concerning "Base time." It is up to us, the player, to understand the mechanics behind it all.

From Wikipedia.....

"Since the 1920s a nautical standard time system has been in operation for ships on the high seas. Nautical time zones are an ideal form of the terrestrial time zone system. Under the system, a time change of one hour is required for each change of longitude by 15°. The 15° gore that is offset from GMT or UT1 (not UTC) by twelve hours is bisected by the nautical date line into two 7.5° gores that differ from GMT by ±12 hours. A nautical date line is implied but not explicitly drawn on time zone maps. It follows the 180th meridian except where it is interrupted by territorial waters adjacent to land, forming gaps: it is a pole-to-pole dashed line."
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Last edited by Front Runner; 01-26-2019 at 12:16 PM.
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