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RedMenace
09-23-06, 10:11 PM
Is there anyway to accurately measure a target's speed without the use of the notebook? I hadn't found one yet.:oops:

Grrbob25
09-23-06, 11:07 PM
you can measure by the way the smoke from the stack is moving or if your good enough, by pure eye


but the average of all lone merchants is between 3-12knts

Dantenoc
09-23-06, 11:41 PM
...are you asking for real?!?!

There are many, many different options: from the basic 3:15 rule, to the use of nomographs, and there's even an elegant method of telling speed by sound from the hydrophones (allthough I don't think it still works in heavily modded games)

Try a look at this helpful start:
http://www.subsim.com/radioroom/showthread.php?t=96026

supposedtobeworking
09-25-06, 02:12 AM
Well while were talking about speed--I use the 3:15 rule which can be found in Wazoo's tutorial if you're interested. It can be very effective in theory but I have found it difficult to get an entirely accurate speed reading myself. Occasionally the distance interval between one of my plots will be very different than most of the other intervals (difference of up to .5 or so km!), and the rest will not quite be the same (within .2 km). I guess this gets you close, but when I hear other people talk about this method it sounds like they can get dead on results...sometimes I wonder if I am doing something wrong (I'm just using the ranges from the Watch Officer precisely in sync with the stopwatch.). There is another method to determine speed by measuring the degrees between the fore and aft of the ship when at closer range, but it demands you be in a good 90 position and close etc. not ideal...Only other one I know of is by sonar which unfortunately doesn't work for me since I use GW.

Also---do you have Wazoos nomograph---look it up on the mod list page and get it! you can then measure speed in other intervals instead of 3:15 (like say 1 min.).

Phylacista
09-25-06, 02:37 AM
heres the direct link to wazoo's tdc manual:

http://www.paulwasserman.net/SHIII/

Skubber
09-26-06, 05:54 PM
I get "dead-on" results with the 3:15 rule. That is to say, the torpedoes go right were I aim them. (At least they do in calm seas ;).)

When I first started playing the game, I thought it was crazy-talk to hear other players say they could target a specific area of a ship. I was just trying to hit a ship!

I suppose it would be more correct from a simulation POV to judge the speed with the hydrophones?

Deep-Six
09-26-06, 06:00 PM
I could not hit the broadside of a barn.

I use automatic settings.:oops:

I am not very good w/ math.:oops:

bert8for3
09-26-06, 08:01 PM
Well while were talking about speed--I use the 3:15 rule which can be found in Wazoo's tutorial if you're interested. It can be very effective in theory but I have found it difficult to get an entirely accurate speed reading myself. Occasionally the distance interval between one of my plots will be very different than most of the other intervals (difference of up to .5 or so km!), and the rest will not quite be the same (within .2 km). I guess this gets you close, but when I hear other people talk about this method it sounds like they can get dead on results...sometimes I wonder if I am doing something wrong (I'm just using the ranges from the Watch Officer precisely in sync with the stopwatch.).

I don't think you're doing anything wrong, I use the same method and as you say sometimes there's an interval which is out of line with the others. I just discard it as having messed up somehow and take another. You do get more accuracy if you do several intervals. I also find that I can be out with the measurement because it jumps by 100 metres at a time, so I generally measure until the cursor just turns to the reported distance, this seems to give more consistency.

Dantenoc
09-27-06, 01:33 AM
I could not hit the broadside of a barn.

I use automatic settings.:oops:

I am not very good w/ math.:oops:

I have found that automatic settings aren't all they're cracked up to be... the computer doesn't get it allways right for some reason (maybe to reward manual settings?).

Redwine
09-27-06, 09:25 AM
Is there anyway to accurately measure a target's speed without the use of the notebook? I hadn't found one yet.:oops:

You can use the Cosin Theoreme to solve it.

If you know two sides of a triangle and the angle between them, with the Cosin Theoreme you can obtain the third side of the triangle, then if you take the time between the two ends of this side you can obtain the speed.

You can do it manually :

http://rotteufel.iespana.es/htdc_tutorial/htdcexercise_006.htm

Or... you can use a Whiz Wheel, a round slider calculator to do it.

Payoff
09-28-06, 02:57 AM
*1. Identify contact. Note Length in rec manual.

*2. Time contact bow to stern with stop watch.

*3. Length divided by seconds = meters per second

*4. Divided by .514 = Knots

Notewire
09-28-06, 05:49 AM
This is a good thread, and gets to the meat of helping us improve as Kaluens.

Payoff, does that work regardless of range? It has been a long time since I studied geometry, but it seems that range would affect knots given the time from bow to stern.

I will say, that I am working on this one myself - as I had been using the 3:15 rule exclusively - but then I started playing with no map contacts - Yikes! Now the 3:15 rule is much harder - as it is difficult to guage the range perfectly. Also, with NYGM - the watch officer doesn't give you uber range estimations. Now I am working on a 6:30 rule, and dividing by two to get speed, but still the Fast 90 shots are very difficult.

Anybody got any good tips?

Laffertytig
09-28-06, 07:23 AM
im having the same problem, im almost tempted to to on the god's eye view to make it easier. how r u supposed to acurately mark targets on the map so u can do the 3.15 rule?

flakmonkey
09-28-06, 07:53 AM
i find the easiest way to measure speed is to simply count the rpm of the ships screws on the hydrophone, works perfectly every time for lone ships or very small convoys (sound is much too confusing in a large convoy though).
theres a great tutorial for this available in the downloads section of subsim (sound trainer mod)

as someone already mentioned some mods may make this not work if they replace the ships engine sounds.

bert8for3
09-28-06, 08:59 AM
... I had been using the 3:15 rule exclusively - but then I started playing with no map contacts - Yikes! Now the 3:15 rule is much harder - as it is difficult to guage the range perfectly. Also, with NYGM - the watch officer doesn't give you uber range estimations. ...

I've been trying to ignore the watch officer's range reports (GW so they show). The stadimeter is tough to get a good range a lot of the time. I've been getting better results I think by putting the vertical hashmark line in the scope/UZO on the target and then getting a read on the target's size in terms of # of hashmarks, i.e. 1 1/2, 2+ a bit etc. Sounds inacurrate, but I think you can eyeball it easier and more accurately this way, rather than trying to hover with the stadimeter. When I get my # of hashmarks, then I click the stadimeter tool on the hashmark measurement to get the range.

Reece
09-28-06, 10:02 AM
You could try my Time-Distance-Speed chart that loads into the Nav map screen, very simple to use but requires a 1.5minute timer (stop watch etc).:) Just download my "Mini Mods", readme doc supplied.
Cheers.
Edit: PS. rename the downloaded file from hyperupload to "Minimods.rar".

Payoff
09-28-06, 11:49 AM
Notewire

Payoff, does that work regardless of range? It has been a long time since I studied geometry, but it seems that range would affect knots given the time from bow to stern.



Yes, this is very accurate, because the boats length is constant. I found this method here at Subsim, I forget the original author. The key is to be as close to 90 degrees AOB as possible. Of course if you are way out in front, with the target coming toward you, it is hard to get a good read. I generally do this three times with great accuracy at all ranges. Just set the crosshairs out in front of the target and man the stop watch. As soon as the bow touches the crosshairs start the watch and follow it through to the stern.
I like this method because it can be done in short peeks, allowing for minimum scope exsposure.

Dantenoc
09-28-06, 07:29 PM
For those who seem to have problems with the 3:15 method on higher realism settings (or even overall), try this link:
http://www.subsim.com/radioroom/showthread.php?t=90234
If you think it's usefull, post on it so other people can have easier acces to it.

Need anoter example? look at the "Video Hunt" thread here:
http://www.subsim.com/radioroom/showthread.php?t=97682
originaly I was thinking about doing more and better video hunt threads, but comunity interest in such threads seemed to die very quickly.

supposedtobeworking
09-28-06, 09:37 PM
Ok, about finding speed by counting the beats on the propellor sounds....is there a way to get this to work in those mods which disable it(i.e. GW 1.1a, etc)?? I think this is a cool feature and would be nice to be able to do...and have asked about it before, but could not get a definitive answer...I tried replacing some files in the sound folder, but I am not sure which ones to replace and what to replace them with. Should I use sounds from stock or from NYGM, i.e. was this feature available in stock 1.4b? I could do some trial and error, but in the event that I can be spared of that does anyone know?? thanks.

Dantenoc
09-28-06, 10:28 PM
stock game with patch 1.4b does support measuring speed with sound.

...as to the mods... well, only the modders themselves can answer that