I think I do not know how a stadimeter is supposed to work. I thought i was giving the range when you had ONE image. This has to be wrong. So what is the PRINCIPLE?

sorry I can't remember which thread--but someone figured it out. IIRC, there is a black line at the bottom of the mirror image. Place this black line on the tip of the highest mast of the actual ship. According to the user, this gives very accurate range.

Ah. So the principle is to JUST and/or EXACTLY see two images? With now space in between?

How did it work in RL?

yes, that is how it worked IRL. The idea though, is not necesserily have "no space" in between the two images. You simply place the mirror image ABOVE the actual ship, so that the water line--where the keel touches the water, of the mirror image, is resting on the tip of the highest mast of the actual ship. Apparently with SHV, they have provided a black line that designates the waterline of the mirror image, which makes it a bit easier. You DO NOT try to "overlay" the image over the actual ship. So it should look like this:

5 (mirror image)
5 (actual ship)

Where the line between the two fives is the waterline of the mirror image placed on the tip of the highest mast of the actual ship.

Thanks! ("Slow" day at work - I have to admit....!)

This really should be covered in the manual!

That is how it worked in real life.
The Stadtmeter uses simple right angle geometry and ratios to find the distance.

***WARNING: MATH!***

Knowing the height of the ship's mast and the angle from your periscope at which that image hits the top of the mast sets up an equation using the tangent of the angle.

Basic Right Triangle Equation:
tangent(angle)= opposite length (height) /adjacent length (distance)

How Equation Applies here
tangent (periscope image angle) = height of ship's mast / range to target

Since you know the first two of the three values in the equation, you can then of course solve for the third - Range to Target.


And as brandtryan stated below you do not have to or WANT to put the image exactly on the of the mast. Depending how fast you are in creating your firing solution and especially if your target is say - a destroyer bearing down on you at 40 knots :o, you can use the stadtmeter to aim ahead of him so that he doesn't outrun your plot. Rather he may very well run INTO it. :D

Likewise for a target like a carrier desperately running away from you at flank, you might dip the Stadtmeter image slightly on top of the real image to make up for the fact that by the time you plot the full solution he could be farther away than when you took the Stadtmeter reading.

The leading with the Stadtmeter is most important when you have to shoot fast with only 1 or 2 readings and perhaps only a best guess at the speed of a target before you engage.

The whole reason that you should normally take 3 or 4 stadtmeter readings ( or more) before firing is so that inconsistencies in any single single reading will be mitigated in the plot of your final solution as more data is entered into the calculation. Getting the speed and AOB right too is of course just as critical.

Ah. It was the mast height that puzled me. I did not know that the game "knows" the mast height! I could not understand how the stadimenter worked with just one value out of three.

I understand how it works if you have 2 out of 3 values. THANKS!

The game "knows" the mast height from the identification book where you have to select the ship type prior to using the stadimeter.

This is why correctly identifying the class of the target is so important. Wrong ship class = wrong mast height
Wrong mast height = wrong equation
wrong equation = "WTF happened to my torps! That plot was perfect! :damn:"

Yes the plot was perfect - had the target been the ship you thought it was :)


Also - can someone please remind me... I have not played Silent Hunter IV for about 6 months now... it's - KNTS = distance in 3 minute right?
ex. ship traveling 500 meters in 1 minute = 15 knts?

everyone has a different method, for example where possible I would track the ship for 3 minutes, measure the distance traveled on the map and the first two digits would give you the speed in knot.

i.e. a ship moving 10 knots will cover 10 nautical miles or 20,000 yds in one hour (1 nautical mile=2,000 yds), in 3 minutes it will cover 1000 yds. If you drop the last 2 zeros you get the speed in knots per hour = 10

now I am going to have to figure it out in metric...:o

3:15 for metric

that may have been me, but I get inconsistent readings.

In SH4, you had a mirror image of the ship and you would lower the waterline of the mirror image to the top mast of the actual image to get the range.

in SH5, they appear to have gone back the the SH3 method (which I have not played since 2007) where you place the thick black line in the middle of the scope on the waterline of the TGT and place a separate thinner horizontal line from the stadimeter somewhere on the ship. I had presumed it was to the top of the mast, but in the last mission I played, I had the most accurate reading from the top of the funnel..:o

Part of the reason may be due to an inaccurate ship identification, some of the freighter classes look remarkably similar.

of course, if the manual actually explained such basic info, we would not have to fumble around like a bunch of clowns trying to figure out this stuff...:damn:

danke

Ah this explains why my calculations were more noticeably less accurate when I started playing with metric in SH: IV.... I couldn't figure out what was wrong but my crew was like,
"Hmm what are you smoking there captain?" :oops: So I switched back to yards and suddenly accuracy improved again and I never messed with it again.

I forgot to switch to the metric for the speed calc! I was still using the yards equation and couldn't figure out why I was completely missing long range shots at slow/med speed targets! I was off by 15 seconds! :rotfl2:

Would you mind elaborating on that please?

Also, which is most authentic anyway? Metric?

Itkovian

In SH3 I use this method to get a ships speed in knots:

1. Ensure you are not moving - engines/motors should be off.

2. Line up your periscope's vertical line just ahead of the passing ship and the moment the bow touches the line start the stop-watch.

3. Do not move the periscope from side-to-side! - Very important! Now, the moment the ship passes and the stern has just cleared the vertical line stop the stopwatch.

4. On paper, or with a calculator enter:

1.94 x ship length (e.g. 125 metres) / (divided by) seconds on stopwatch. (e.g. 45).

So, 1.94 x 125 / 45

The above would give you a speed of 5.38kts for a ship of 125m in length.

This method works at quite a varied angle when viewing the ship, so you don't necessarily need to be 90 degrees from her.

I usually take 2 measurements to be on the safe side, especially with convoys.

Hope it helps! :up:

Px3000

Hmm that is an interesting method. I'll have to give that a shot.

Let me just clarify one thing:

Lets say you're lining up a bow on shot - angle on bow is 45 degrees or less - so he's coming almost right straight at you.

Do you start the stopwatch when the center of the bow hits the line, or do you start it when one side of the bow hits the line?


AKA START:
|\___/ HERE

or

\__|__/ HERE


and stopping \___/| HERE

Thanks for sharing!

Yards traveled in 3 minutes divided by 100 gives speed in knots

Works the same way for metric but you need to use 3 minutes 15 seconds.

Hi,

I try to be at least 60-70 degrees to the ship when taking the measurements so that the bow is noticeable. It doesn't work with 'head on' shots as you need to let the ship pass the line for the measurements to be taken.

However, saying that I have measured from 40-45 degrees in the past and whatever part of the ship hits the line first I go from there. I will then take a second reading about 5-minutes prior to firing to ensure she hasn't increased (or decreased) speed and the difference between the 2 figures is often tiny.

It always gives me accurate speeds, but you must ensure you have accurately identified the ship and obtained the correct length. If you get it wrong, and enter a wrong ship length the calculation will be incorrect and you will get the wrong result.

Give it a try and good luck! :salute:

Px3000

Well metric would be authentic - as it's what the Europeans use for measurements.

But I would think that you could go with Phoenix3000's equation below and be just as "authentic". There's little doubt in my mind that a competent U-boat skipper would have used any tricks up his sleeve possible for calculating a firing solution. I mean, they had to be adaptable for the situation and one tactic that works against a lone liner, doesn't necessarily work for a convoy, or a destroyer escort hell bent on turning you into a big black oil slick.

Now if you wanted to be "SUPAR AUTHENTIK!" TM, use Phoenix3000's equation and instead of using a calculator, do it with pencil/paper OR actually use a slide rule! :DL