Stadimeter range is off (Bug?)

[Krupp]

Originally Posted by FinnN

This means that the height of the flight deck would be the most reliable way of measuring the range of carriers. Possibly this is where the different spotting locations are coming from.

If so, why didn't they do so for every carrier in the game? And if intentional, why there is wrong measures in every dimension for some ships, lenghts, widths etc? They have nothing to do with the firing data. Some lenghts are way of. Also, why the dev's say in the manual: "...you need to have the waterline, as viewed in the second picture, touch the masthead of the first one."

[Bilge_Rat]

So what is the consensus, is it caused by using a widescreen and non-standard resolutions or not?

I had no problems in 1.1, but rarely shoot at ranges greater than 1,000 yds.

In 1.2, I use 1280x960, which is a 4:3 resolution, although the only torpedo I fired so far was at the Mogami in torpedo school.

[NefariousKoel]

I'm gonna give Krupp's mod another go and see how much of a difference it makes.

[Egan]

I'm using 1600 by 1200 (4:3) and I hadn't tried using the sonar man to ping distance before so I went to test it. I set up an attack on a stationary 'Old Composite Merchant' and closed in from a long way out. I was getting quite a big discrepancey between the sonar ranging and stadimeter when i measured from the top of the mast. Closer in, I lowered the stad a bit more, checked my distance with the sonar and the two finally started getting close to one another.

So for me, yes, there does appear to be something wrong here. I think Krupp is probably on the right track with mod but i remember someone saying that using the Observation scope gave far more accurate results than either the attack scope or the TBT.

[AVGWarhawk]

Originally Posted by Egan

I'm using 1600 by 1200 (4:3) and I hadn't tried using the sonar man to ping distance before so I went to test it. I set up an attack on a stationary 'Old Composite Merchant' and closed in from a long way out. I was getting quite a big discrepancey between the sonar ranging and stadimeter when i measured from the top of the mast. Closer in, I lowered the stad a bit more, checked my distance with the sonar and the two finally started getting close to one another.

So for me, yes, there does appear to be something wrong here. I think Krupp is probably on the right track with mod but i remember someone saying that using the Observation scope gave far more accurate results than either the attack scope or the TBT.

Just to throw a wrench in , at very long distances, what your simulated Stadi and your eye can see will be very much different than a definite sonar ping and time the sound travelled back. As you get closer, the stadi gets more clearer just as the ship get more clear and the mast can be seen quite readly. At this point the stadi should be accurate and close to what the sonarman is telling you. How can any accuracy by eye and a shaking scope/TBT be gotten from 5000 yards off?

Just my thought.

[Egan]

I'm pretty sure I shouldn't be 1500 yards off..

But as I said, even close up there was a very obvious discrepency between sonar and stadimeter. Only when using the stadimeter well down the mast on the particular merchant did the two ranges finally match. At 5000 yards or greater you are right - there shold be a degree of error. At less than half that, though, the error should be much less.

Anyway, I've only started testing this. I'll set another one up with the same type of ship at various ranges that are known to me and see what transpires.

[AVGWarhawk]

I do play at 1024x768 so this might be the difference. I'm really not sold on the greater resolution play while in game. Sure, picture is higher res but has the number to make the game run also compensate for this???:hmm:

[Radtgaeb]

Originally Posted by Krupp

Sure, the masts are jaggy and it's hard to see the exact top time to time ( which is a good thing ), but you'll get at least guesstimate of the range which is enough and this brings some natural uncertainty to the range estimates. Not any artificial nonsense about measuring this or that mast from different heights or cross trees etc.

Main thing is, that that is the mark (mast top) were the stadimeter should be pointed every time (not some odd part of the mast or ship). And it gets easier as the target comes closer. You should be able to rely the fact, that the aiming point is alway the same (to get correct range), which is not the case in the SH4 (without modding the ship data).

Actually, no. I never have a very good estimate. It's always way short or way over. It never works for me unless I'm within 800 yards or so.

[Krupp]

Originally Posted by Radtgaeb

Actually, no. I never have a very good estimate. It's always way short or way over. It never works for me unless I'm within 800 yards or so.

Actually, yes. I usually almost always have very accurate range estimates with the stadimeter (using the JP Ship Dimension Fix mod). If you are using it too and still have some range problems, then it might have something to do with the screen resolution, not sure tho. 1440 x 900 it works very well. If you're not using the mod, I am not surprised that your ranges for some ships are incorrect. By saying "It never works for me" tells me that you are using the mod. What can I say? I have tested all the jap ships in the game at least three times with the mission editor and I have nearly perfect range measures. And the torpedo hit rate is very high in the game, so I can't complain. Naturally I hope that it would work for all who wishes to use it.

[buteobuteo]

If you are using the WO to get ID then the Stadimeter will not be accurate as the Mast Height will not be entered on the dial.

[Krupp]

Originally Posted by buteobuteo

If you are using the WO to get ID then the Stadimeter will not be accurate as the Mast Height will not be entered on the dial.

Another thing is that WO doesen't give you the correct range to target, it is about 10% shorter that it should be.

Also, the game stadimeter doesen't convert metric distances to yards when you choose to use imperial scale. Even with the imperial scale, the range to target is in meters.

[akdavis]

Originally Posted by nattydread

I suspect the stadimeter is inaccurate at range by dev design in part. The detail on ships atrange is reduced enough to make accurate distance claculatioons difficult, espeically considering the limited fidelity/resolution in the adjustment of the stadimeter. Basically at range the masts arent rendered very well. It makes range calculations very loose until the ship is close and fully rendered in higher detail with masts accuratly rendered and the stadimeter's limited fidelity/resolution of no consequence.

No, I don't think that is the intent. If the correct mast height is used and conditions allow for a precise reading of angle, there is no reason there should be error in the returned range. That would be like introducing a math equation that only works sometimes. Furthermore, a system in which you have the same error at close range as at long range makes no sense. The limited resolution of the screen and tool when rangeing on distant targets already introduces a great deal of error.

If they wished to introduce rangeing errors, there would be more logical ways to do so.

[MudMarine]

Shippers,

I think the devs purposely place error in the stadimeter. Even then in 1950 rnage was off plus or minus 35 yards. I think the devs used this manual for thier model.
Also you will find other factors. Funnel smoke obscuring the mast, intentionly heighten or shorten by the enemy, camoflaged or the water line obscured at long range by the horizen.

I believe the devs got it right. If they used the manual I have posted a link to has been used aas a reference. So given the info in the manual the devs have designed in a fudge factor in the stadimeter to reflect what they got from this manual.

Submarine Torpedo Fire Control Manual
http://www.hnsa.org/doc/attack/index.htm


Exerpt from: Submarine Torpedo Fire Control Manual Cia 1950:



(e) Of the three methods the radar ranges are the most accurate and depend primarily upon the adjustment of the radar which is usually plus or minus 35 yards. The accuracy of telemeter or stadimeter

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ranges depend first, upon the skill of the observer and second, upon the accuracy of the estimate of target masthead height.

(f) The value of the masthead height of the target may be obtained by intelligence, estimate, or by a method referred to as "radar stadimeter" (telemeter) estimate. The latter of course is the most accurate and is accomplished as follows; assuming that the target has been tracked using the ST periscope, the Type II periscope is raised immediately following an ST periscope observation, a stadimeter range observation is made as described above, but instead of reading range on the scale, the masthead height is read opposite the value of the TDC generated range.
(g) When radar ranges cannot be obtained the Approach Officer must rely upon his ability to correctly estimate the height of the funnel or masthead, or other prominent mark on the ship's structure above the water line. If the target ship can be properly identified an accurate value may be obtained from intelligence information supplied the ship. If this is not available the following procedure will he of assistance:


(1) Count or estimate the number of decks that are seen above the main deck.

(2) Add to this figure the approximate number of deck heights equal to the observed freeboard.

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(3) Multiply the total by eight to determine the height of the top of the bridge structure above the visible waterline.


(4) Using height of bridge structure above the visible waterline as a yardstick, approximate the masthead height. The masthead heights of merchant ships are on the average about 2.1 times the bridge height (above waterline). A masthead height which appears to be shorter than normal will be about 1.7 to 1.8 times the bridge height, while one which appears to be higher than normal is approximately 2.2 to 23 times the bridge height.

(5) Funnel heights may be estimated by approximating the number of deck heights of the funnel which is seen above the top of the bridge structure and adding this height to the bridge structure height.
(6) At extreme ranges it must be remembered that the waterline is below the horizon. This necessitates estimating the position of the waterline.

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(h) The following points should be kept in mind in height determination:
(1) Masthead heights may be purposely altered by the enemy to cause inaccuracies in periscope ranges.


(2) Tops of masts may be camouflaged in such a manner as to be invisible under average visibility conditions at any except short ranges.

(3) Funnel height is normally sufficient to insure that the smoke which is blown in the direction of the bridge by a tail wind will pass well over the bridge.

(4) Coal burners require taller funnels to insure adequate draft.

(5) Funnels of modern vessels having forced draft do not require as tall a funnel as older vessels without forced draft.
(6) Diesel propelled ships require no draft. Funnels are normally short, are not required, and generally have such dimensions as to provide a good appearance on the ship.



Regardless of the methods employed by the individual Approach Officer, skill in estimating masthead heights, and ability to obtain accurate ranges can

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be acquired and maintain only by constant practice. Even when radar ranges are available daring an approach the Approach Officer should also obtain telemeter ranges as a means of improving and maintaining his skill.

With that said the Devs may have just ot it right. I would not complain about this feature. The target book in meters instead of imperial on purpose? I think so.

So for those realism buffs think about it. This exerpt explains a lot.