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danmir · 06-14-07, 01:57 PM

I really like having the map updates off myself. I have been playing with it off and 100% difficulty with mixed results in performance, but lots of fun.

My nitpicks on realism:
- With the scope stabilization off: I have a hard time believing the scope would roll around as much as it does in game, considering I'm down 15m below the waves. I could be totally wrong but I think it would be much less bobbly.

- The optics in general. From accounts that I read, sub captains were able to make out masts fairly well at the horizon and keep just the tops visible. In game at that range, you can't really see anything but the smoke. Also, I get the impression a real sub commander's optical viewing yields more detail than you get in game (as far as determining ship type, course, AoB, etc).

=====================================

For fun on a related note...some math on horizons. Consider the horizon is tangent, so you have a 90 degree angle there to the earth's radius. (wish I had a drawing!). Thus you have a right triangle formed by the earth's radius + your height, the radius of the earth itself, and the horizon length.
(Rearth+height)^2=Rearth^2+horizon^2
horizon^2=(Rearth+height)^2-Rearth^2
horizon^2=Rearth^2+2Rearth*height+height^2-Rearth^2
horizon^2=2Rearth*height+height^2
horizon^2=height*(2Rearth+height)
horizon=sqrt(height*(2Rearth+height))

Rearth~=6871300 m

horizon=sqrt(height*(2*6378100+height))

Noting that 2*6871300 + height ~= 2*6871300 for small heights,

horizon~=sqrt(height*(2*6378100))
horizon~=3571.6*sqrt(height) (all in meters)
horizon~=3.572*sqrt(height) (height in meters, horizon in km)

Good rule of thumb that takes into account refraction:
Horizon in km is 3.9*sqrt(height).

The same will of course apply to your target from the top of his mast.

Thus the earliest you could possibly see a target is your horizon distance plus the top of the mast horizon of your target. This is the case when you are both along the tangent line just over the surface of the earth.

Playing with the numbers: Say we are at a height of 5 meters in the sub's conning tower. Our horizon is about 8.7 km away. Say a target has a 22 meter mast. The horizon 22m up is 18.3 km. You should just see the top of the mast then at a range of about 27km.

06-14-07, 01:57 PM	#7
danmir Swabbie Join Date: Jun 2007 Posts: 12 Downloads: 0 Uploads: 0	I really like having the map updates off myself. I have been playing with it off and 100% difficulty with mixed results in performance, but lots of fun. My nitpicks on realism: - With the scope stabilization off: I have a hard time believing the scope would roll around as much as it does in game, considering I'm down 15m below the waves. I could be totally wrong but I think it would be much less bobbly. - The optics in general. From accounts that I read, sub captains were able to make out masts fairly well at the horizon and keep just the tops visible. In game at that range, you can't really see anything but the smoke. Also, I get the impression a real sub commander's optical viewing yields more detail than you get in game (as far as determining ship type, course, AoB, etc). ===================================== For fun on a related note...some math on horizons. Consider the horizon is tangent, so you have a 90 degree angle there to the earth's radius. (wish I had a drawing!). Thus you have a right triangle formed by the earth's radius + your height, the radius of the earth itself, and the horizon length. (Rearth+height)^2=Rearth^2+horizon^2 horizon^2=(Rearth+height)^2-Rearth^2 horizon^2=Rearth^2+2Rearthheight+height^2-Rearth^2 horizon^2=2Rearthheight+height^2 horizon^2=height(2Rearth+height) horizon=sqrt(height(2Rearth+height)) Rearth~=6871300 m horizon=sqrt(height(26378100+height)) Noting that 26871300 + height ~= 26871300 for small heights, horizon~=sqrt(height(26378100)) horizon~=3571.6sqrt(height) (all in meters) horizon~=3.572sqrt(height) (height in meters, horizon in km) Good rule of thumb that takes into account refraction: Horizon in km is 3.9*sqrt(height). The same will of course apply to your target from the top of his mast. Thus the earliest you could possibly see a target is your horizon distance plus the top of the mast horizon of your target. This is the case when you are both along the tangent line just over the surface of the earth. Playing with the numbers: Say we are at a height of 5 meters in the sub's conning tower. Our horizon is about 8.7 km away. Say a target has a 22 meter mast. The horizon 22m up is 18.3 km. You should just see the top of the mast then at a range of about 27km.