Where do you stand on Map Updates?

[maillemaker]

Yeah, I've been wrestling with this while watching all these "100%" realism posts.

I tried it myself, and it was a little underwhelming to me.

First, I've turned back on the auto TDC. I found I could, in fact, sink ships without it, but to me the biggest problem was identifying ships. It just took too long to ID a ship. I think a real submarine captain would not be thumbing through the ID book - he would know on sight. So to me it is probably more realistic to have the auto ID on. If it would just do the auto ID, I could do the range and speed calculations myself.

So I turned the auto TDC back on. Maybe as I get more experience looking at ships I will be able to ID them by eye rather than having to use the ID book. The ID book is very slow, I find, to click from page to page.

I tried running with no Map Updates, but to me this is like sailing blind. I'm the Captain, dang it, and I expect my crew to keep track of things like contacts. I don't want to have to "do it all", running the hydrophone, checking the periscope, and tracking the positions on the map.

So I've got everything off except external view, auto TDC, and Map Updates.

The external view, well the game is boring just watching pole-dancing sailors in my sub - I like the view. The TDC compensates for my lack of nautical experience to identify ships. And the Map Updates just makes the game far less tedious.

So that's me.

[danmir]

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).


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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.

[ichso]

The scope view was more often than less too bouncy, I agree on that. But it feels like it is more stabilized since GWX 1.03 or am I wrong there ?
But it's true, we are driving submarines and not nutshells which get shaken by every little wave

[danmir]

I'm wondering about the visual acuity so I looked it up. See if you guys think these numbers are right. Wiki lists 20/20 vision as being:

"20/20 is the visual acuity needed to discriminate two points separated by 1 arc minute"

I assume it means 2 points seperated by 1 arc minute at 20 feet.

20 feet * 12 inches/feet* 2.54cm/inch * (1/100 m/cm) = 6.096 meters

Considering a right triangle approx, you get 6.096*sin(1/60)= 1.77325449502e-3 meters ~= 1.8mm

It means with 20/20 vision: at 20 feet (6.1m), you can distinguish 2 dots 1.8mm apart.

So what about at say 8 km? You have similar triangles, so

8000/6.096 = x / 1.77325449502e-3, x=2.32710563652 m

Thats about 2.3 meters of resolution at 8 km with the naked eye. I haven't done the math, but I'm confident that at the default 1024 resolution we are not getting about one pixel every 2.3m of a 8km distant ship. And this is with the naked eye view.

I don't have the game in front of me, so I can't give evidence. Though consider a typical ship length of say 100m and beam of 15m. I'd expect it to extend 43 pixels from the side, or 6.5 pixels looking at it from the bow or stern. (at 8 km range). If we make the assumption that each pixel is one of the "seperable dots" as defined above (in reality, two dots, pixels next to each other are blurred, so it would take at most a pixel between to squeeze in a gap between two dots. I say at most because I think you could bring them closer, and with shading the area between with antialiasing, the two as dots may still be distinguildable.).

My monitor has a 20.1" diagonal, say a 4:3 aspect ratio, so its about (3-4-5 triangle) 16.1" across. This means each pixel is 0.01572265625". So it would extend 0.67607421875"(1.72cm) looking along the port or starboard (90d aob) or 0.1" at the bow or stern. I'll have to measure in game, but I'm confident that at 8km, a 100m long ship is not 1.72cm long in a naked eye view @ 90d AOB. Thus we are losing resolution.

If you have an optical aid, as long as its aperture is bigger than the eye, and it has passable optical quality, it will improve your resolution. So think of 2.3m@20km as a worst case. With binos, you'll likely have much better resolution. I would expect it at the upper limit to improve by the ratio of the area of the area of light gathering aperture of binocs / area of your pupil. Considering a typical pupil diameter of only 3-8mm, it seems there is much room for improvement with binocs.

In conclusion, I think the monitor costs us resolution and the real eye, especially aided with binocs would give much better detail on ships at range.

[joegrundman]

Of the low-realism options, I only ever use external view, and then only on every other patrol in order to deter bad habits. But i like the pretty pictures. My average tonnage score isn't affected - i think.

I do not use map contact updates, ever. I only used it when learning how to do manual targetting. That sort of situational awareness was impossible without modern computers, but i do kind of agree that the current following options provided by the sonarman are inadequate. You ought to be able to specify follow nearest merchant contact, because if you are tracking an approaching convoy, the nearest contact is often the lead escort performing a search pattern, which is much harder to track than the convoy, so i have to spend time in the hydrophone station myself.

I also think that it would be better if the sonarman could track more than one object at a time for you. Perhaps the number of trackable opjects would be proportional to the experience/skill of the operator, but this is obviously out of the question until the next gen SH game is released.

Stabilise view was the last thing for me to graduate out of. As for its historical veracity, well the u-boat may be moderately stable, but the scope is on the end of a long arm sticking out from the sub. Even tiny rotations in the sub will translate as severe movements in the scope head, especially if the view is then magnified.

In any but very calm weather, accurate range readings are therefore impossible and determining course by plotting is not recommended. They found it too difficult and unreliable in real life and didn't do it then either. But AOB is still easy enough to determine visually in rough weather, and that coupled with a poor range reading is far more accurate than plotting using two inaccurate range readings.

All this is made easier using a SACF or kriegsmarine equivalent whiz wheel. In my sig there's a link to my hunting method which never requires multiple plotting to determine target track, and therefore works well in bad weather.

As for IDing targets, practice!! Also, experience can often tell you in advance the kind of target to expect in any given area and time and you can have the recognition manual prepared and at the most likely page before you get close enough to make a positive ID. it is also the case however that for range reading purposes, you don't have to have gotten it completely correct. Most destroyers have a similar mast height. Small and coast merchants have a simillar mast height. C2 and c3 tankers, likewise - but in this case the truth should become apparent eventually and you can make the necessary corrections. It's enough to be getting along with.

My suggestion for improvement to the game in this regard is that when in the museum, it should show you the present AOB from every position so that players can familiarise themselves with how the targets look from different AOBs

[dcb]

Originally Posted by ichso

But it's true, we are driving submarines and not nutshells which get shaken by every little wave

It's not the sub that's being unstable. On the contrary, it is actually too stable - LOL. So stable that if the peri always stays at the same depth, waves however are of different heights. In brief, what you take as sub instability is the waves (higher or smaller) that constantly wash your periscope.

[Sailor Steve]

Originally Posted by ichso

I So is it possible to leave just the sonar contacts on the map on and visible contacts not ? The whole plotting-by-sighting thing is cool.

*wave*

Read my post two above yours, #5. The Assisted Plotting Mod does just that. It comes with Real U-Boat by Beery. http://www.subsim.com/radioroom/show...ht=Real+U-Boat RUB's readme lists exactly which files were changed to achieve different ends, so you can take just the files that affect map contacts. This is what I did (I run a bunch of different mods from different collections, combined to suit my own tastes. Assisted Plotting is the most realistic to me).

[ichso]

It's not the sub that's being unstable. On the contrary, it is actually too stable - LOL. So stable that if the peri always stays at the same depth, waves however are of different heights. In brief, what you take as sub instability is the waves (higher or smaller) that constantly wash your periscope.

The point is not about waves washing my periscope but about a steady aim. For example to place the horizontal line of the stadimeter correctly and getting an accurate reading from the scale. This much more difficult when the periscope goes up and down all the time.

[Sawdust]

Originally Posted by ichso

For example to place the horizontal line of the stadimeter correctly and getting an accurate reading from the scale. This much more difficult when the periscope goes up and down all the time.

I made some tables you can use to get range in SHIII without the use of the stadimeter. You might find them useful. They are at http://www.brockmanonline.com/sh3/sh3.html

[ichso]

Already got them
They look very good, though I was too lazy to print them out yet