Well, I've been testing and I have found that Frame Rate Limiting does not give the same results as Vertical Sync Rate limiting as it relates to the In-Game Celestial Sphere synchronization.
My initial results show that when I have my Nvidia Control Panel settings set to my monitors' native resolution of 1920x1080 @ 144 HZ with the Nvidia Profile Inspector set to Frame Rate Limit of 30.5 HZ and In-Game V Sync ON, and CNTRL/F8 shows a In-Game frame rate of ~30, I am getting 1X play differences which are very large compared to setting my Nvidia Control Panel to 1920x1080 @120 HZ and using the Nvidia Profile Inspector Vertical Sync @ 1/4 refresh rate (30 fps in game.)
I am still drilling down on it but it appears to me that Frame Rate Limiting does not help synchronize the Celestial Sphere.
My current setup is as follows-
1. My ASUS monitor is set using Nvidia Control Panel to 1920x1080 @ 120HZ
2. My Nvidia Profile Inspector Vertical Sync Rate is set to 1/4 Refresh Rate
3. My Nvidia Profile Inspector Frame Rate Limiter is OFF
4. My In-Game Graphics settings match 1920x1080@120HZ
5. My In-Game Vertical Sync is ON.
6. In-Game FPS = 30
After 1X for more than 96 hours my Sunset is only a few minutes off of the Almanac prediction. It is tracking more or less perfectly.
My previous set up was as follows-
1. My ASUS monitor was set using Nvidia Control Panel to 1920x1080@144HZ
2. My Nvidia Profile Inpector Vertical Sync was set to "Use the 3D application setting."
3. My Nvidia Profile Inspector Frame Rate Limiter was set to 30.5 fps
4. My In-Game Graphics setting matched 1920x1080@144HZ
5. My In-Game Vertical Sync was ON.
6. In-Game FPS = ~30
After 1X for more than 72 hours my sunset was 40 minutes later than the Almanac prediction. Not good.
*NOTE - In-Game Graphics settings take control so it appears to be unnecessary to pre-set the Graphics using Nvidia Control Panel. Whatever you set In-Game takes precedence over Out-Of-Game settings. In other words, I can just leave my Nvidia Control Panel set to 1920x1080@144HZ and the In-Game settings will override. I can set my In-Game Graphics to any of the highlighted options. In this case I chose 1920x1080@120HZ so that 1/4 Refresh Rate = 30 fps.
I know, what does this matter in standard game play? Well, the reason I bring it up is because I'm not sure that the Anti-Lag Mod for non-Nvidia cards is actually syncing the Celestial Sphere as it limits the Frame Rate to 30 as compared to limiting the V-Sync rate to 30 by other means. In my case, forcing V-Sync to 1/4 refresh rate by using 3rd party Nvidia tools.
I'm well into my 4th day at sea at 1X play and the Celestial Sphere is tracking damn near perfect! Especially the Sunsets. Sunrise, Moonrise and Moonset are within acceptable ranges of Almanac predictions.
Useful information Frame Rate Limiting vs Vertical Sync Limiting.
https://forums.tomshardware.com/thre...ained.2272294/
Since the US Navy Sunset/Sunrise website is off-line until late next spring,(now indefinite due to COVID-19) I've discovered another Sunset/Sunrise Moonset/Moonrise Calendar which fills the need. Here.....
https://www.sunrisesunset.com/custom.asp
NOTE: Sept. 23, 2022 - See FIRST POST for the NEW US Navy Sunrise/Sunset LINK