The Silent Hunter 4 TDC discussion

heartc · 03-21-07, 10:51 AM

TDC instructional video:
http://www.subsim.com/radioroom/showthread.php?t=108689

Well, they almost got it. Almost. They made one small mistake which however has a big negative effect on the usefullness of the position keeper.

Take a look at the lower dial of the position keeper. You will notice it displays and updates the GYRO ANGLES (just like the green line on the attack map) but instead it should be the TARGET BEARING.
There are two ideas behind the position keeper: It should continuesly update the fire solution, taking ownship movement into account (which it does perfectly), but it should also continuesly provide the target position (via bearing and range). Without a bearing readout, we miss a MAJOR feature of the TDC: iRL and in SHI, you were able to CHECK your fire solution after entering the data by watching whether or not the actual target bearing that you can see through the scope and the TDC bearing readout stayed the same. If those two bearings started to drift apart, you knew your solution was not the best, and the faster they drifted apart, the worse it was and you knew your torps are going to miss. If it stayed the same or differed only slowly, you knew the solution was pretty accurate at least if you fire soon and the range was not too great in the later case (when differing slowly).

If the solution was bad, you could easily adjust it by changing target speed, i.e. if the target crosses your periscope bearings faster than your TDC showed, you had to increase target speed for example and vice versa.

The funny thing is that actually in the manual of SHIV when you check the TDC description section you will read them describing that possibility of "checking" the accuracy of the solution and INDEED, where we now have the Ship name read out in the header above the two dials, on the pic in the manual there is this readout: "Target 10, 010" and indeed the lower dial also shows the bearing of 010, not GYRO ANGLES as it does now. It baffles me that they changed that and I wonder why.

A small work around might be to note the difference between gyro angles and actual bearing and watch out that this difference stays the same, however this is inaccurate, needs you constantly calculating and would work only for a rather short time since the difference *must* change over time.

Otherwise I think the game is in fact awesome. Especially cause I didn't even know if it will run at all since I'm only on 1.8 GHz, 512 RAM and 9800Pro, but in fact it runs better than SHIII for me (time compression way better, loading times shorter, runs fluid with some settings I don't care for anyway turned off and the gfx card tuned for performance in the control panel). But I hope they correct the TDC, because being able to actually check your solution for accuracy before firing was a MAJOR feature iRL and in SHI.

elanaiba · 03-21-07, 11:18 AM

I'm not sure I get the problem right

The arrows superimposed on the lower dial mark the gyro angle for the selected torpedo tube.

But the bearing to the target is read on the top of the line. Draw a line between the centers of the upper and lower dials and the intersection with the two dials will give you the AOB (for the top one) and the bearing (bottom one).

On a dial, read the "relative" value on the inner ring, and the "absolute" value on the outter ring.

See this scan from Norman Friedman's book "Us submarines" through 1945".

heartc · 03-21-07, 11:31 AM

Holy crap. That might well be right. I'm not sure if I'm with you, but I have some idea and will have to check it out asap.

Thanks for providing the image scan! Too bad sims do not come with proper manuals anymore, might have spared me from possibly submitting false claims.

If a mod reads this, please go ahead and flag the topic as "Resolved" or something, since my change of the header is only visible inside the thread. Thanks.

heartc · 03-21-07, 09:43 PM

Nope, I'm afraid my initial observation is indeed right. I just checked it out again in-game. Take a look at the image scan elanaiba provided. What we do have on the position keeper in game are the two lower right hand dials. What we do NOT have is a RELATIVE TARGET BEARING (not TRUE BEARING) readout, something similar to what you see on the right hand side in the upper half of the image - actually a numerical readout where it says "Bearing Degrees". We need a TDC output for relative target bearing so that we can compare relative (sighted) target bearing with computed relative target bearing. When you look at the image scan again, you can even see a "Bearing Error" readout which assisted in determining the solution error. We don't neccessarily need this since it would be redundant, but sure enough for the position keeper we need a RELATIVE target bearing output.

Hasn't anybody else noticed this or am I really missing something here? SHI had it, too, as a numerical readout similar to the one in the image.

In fact I think what elanaiba said might indeed be right, I will check again some time later, but then it is a VERY arkward and highly inaccurate (since hard to read) way for the game to provide relative target bearing, especially when we are talking about small deviations between sighted and computed relative bearing which is the nature of the whole checking technique.

Arrowhead2k1 · 03-21-07, 09:48 PM

You're absolutely right. It would be awesome to have a way to check your solution without having to fire a shot aswell.

nattydread · 03-21-07, 10:02 PM

I have to admit, I was concerned there would be some mistakes going from the U-boat TDC to the US TDC, being that SHIV seemed more or a less a re-dressing of SHIII. I hope they resolve it soon. Things like this makes the difficulty in finding the game not so frustrating.

heartc · 03-21-07, 10:13 PM

Quote:

Originally Posted by Arrowhead2k1

You're absolutely right. It would be awesome to have a way to check your solution without having to fire a shot aswell.

Yes, and it's also how they did it iRL.

It was the second most important function of the TDC.

At first I didn't notice it and thought "hey look, seems they got it right", but then after I entered the data for my first target (I went right into the campaign), I was like "Uhm. OK, now where is the bearing? Where is the bearing readout??"

Really, what makes me wonder the most is when you check out the manual and look closely at the image provided in the TDC description section, you WILL see a numerical relative target bearing readout in the "header line" where we now get the ship type provided instead after ID'ing, and they TALK about the Position Keeper helping in checking and fine-tuning the solution.

ParaB · 03-24-07, 06:38 AM

One thing that's really driving me crazy is the constant resetting of torpedo settings in the TDC (full manual targetting). I set all forward torps for fast speed, impact detonator, set spread angle and depth. Then I open all torpedo doors. After a short time I hear clicking noises and the detonator has switched back to magnetic, as well as screwing over my angle input. The torpedo depth seems to stay as input.

Another annoyance: the tube doors seem to close again each time you choose another tube. In SH3 I could use the 3d-switches to keep the doors open, in SH4 there aren't any anymore...

PLEASE, dear devs, fix this.

divo 637 · 03-24-07, 03:32 PM

The original poster is correct. This is not working correctly. The issue is that it will work correctly sometimes then stops working.

The PK should mimic a LOS diagram. So that own ship will not always point straight up.

The Own Ship ring (the bottom one) should point to the true bearing to the target at the top. And the target ring should point to the true bearing of your ship (so 180 deg out from where own ship ring points).

The bug somehow forces a relative bearing of 0 to the top of the ring.

Watch the training video that is a sticky. It works fine at the TBT and when he goes below to the scope it works fine for a few seconds then it abruptly jumps to the realative bearing of zero at the top of the ring and does not change on the next several updates. You have to be looking for it. It happend quite fast.

This may have something to do with the inputs to the PK so that UbI had designed in some criteria on the way this work (maybe something about bearing inputs). Not sure. but this needs to be fixed.

Spectre-63 · 03-25-07, 01:33 AM

HI all -

started a second career today using manual TDC and things did not go nearly as well as I'd hoped.

The first thing I noticed was that virtually all of my range estimations (using the stadimiter) were well short of the target's actual range. I think I'm using it correctly: setting the horizontal line in the periscope along the waterline of the target, selecting the correct ID in the recognition manual, bringing up the image splitter/stadimeter, and placing the waterline in the top image on the top-most point in the bottom image. At first I thought I was mis-identifying the targets, but the sampan fishing trawlers couldn't be misidentified because there was only one with the correct number of sails.

The other thing I noticed is that, over time, the position keeper appears to get confused as to where the target actually is. The only thing I can think of is that my constant re-configuration of the target info is confusing it?? The lack of a functioning chrono is certainly hurting my speed estimates, but I think I can overcome that. I've got the 'turn off map updates' off, so I'm cross-referencing where the target appears on the map with where the TDC thinks the target is (white X with a tail indicating direction of movement).

Any assistance would be greatly appreciated!!!

Seadogs · 03-25-07, 04:43 AM

Quote:

Originally Posted by Spectre-63

I've got the 'turn off map updates' off, so I'm cross-referencing where the target appears on the map with where the TDC thinks the target is (white X with a tail indicating direction of movement).

I am using the same method to train myself on manual TDC. It works great. I'd say it works even better than auto tracking.

Having problems with my ranges too tho. Using the method above I can easily correct it, but I don't plan on playing like that forever.

Can anyone provide a good zoomed screeny of perfect standimeter alignment? It would help alot as I think it's an issue of finding the sweet spot.

ryuzu · 03-25-07, 06:02 AM

Quote:

Originally Posted by Spectre-63

HI all -

started a second career today using manual TDC and things did not go nearly as well as I'd hoped.

The first thing I noticed was that virtually all of my range estimations (using the stadimiter) were well short of the target's actual range. I think I'm using it correctly: setting the horizontal line in the periscope along the waterline of the target, selecting the correct ID in the recognition manual, bringing up the image splitter/stadimeter, and placing the waterline in the top image on the top-most point in the bottom image. At first I thought I was mis-identifying the targets, but the sampan fishing trawlers couldn't be misidentified because there was only one with the correct number of sails.

The other thing I noticed is that, over time, the position keeper appears to get confused as to where the target actually is. The only thing I can think of is that my constant re-configuration of the target info is confusing it?? The lack of a functioning chrono is certainly hurting my speed estimates, but I think I can overcome that. I've got the 'turn off map updates' off, so I'm cross-referencing where the target appears on the map with where the TDC thinks the target is (white X with a tail indicating direction of movement).

Any assistance would be greatly appreciated!!!

Did you check what measurement units the stadimeter is giving you?

If you're using imperial measurements, the units on the stadimeter dial are yards - not feet... There are 3 feet in a yard.

Oh, and the stadimeter measurement is supposed to be done while the scope is at high magnification (although this would lead to over rather than under reading).

r.

Spectre-63 · 03-25-07, 02:53 PM

Quote:

Originally Posted by ryuzu

Quote:

Originally Posted by Spectre-63

HI all -

started a second career today using manual TDC and things did not go nearly as well as I'd hoped.

The first thing I noticed was that virtually all of my range estimations (using the stadimiter) were well short of the target's actual range. I think I'm using it correctly: setting the horizontal line in the periscope along the waterline of the target, selecting the correct ID in the recognition manual, bringing up the image splitter/stadimeter, and placing the waterline in the top image on the top-most point in the bottom image. At first I thought I was mis-identifying the targets, but the sampan fishing trawlers couldn't be misidentified because there was only one with the correct number of sails.

The other thing I noticed is that, over time, the position keeper appears to get confused as to where the target actually is. The only thing I can think of is that my constant re-configuration of the target info is confusing it?? The lack of a functioning chrono is certainly hurting my speed estimates, but I think I can overcome that. I've got the 'turn off map updates' off, so I'm cross-referencing where the target appears on the map with where the TDC thinks the target is (white X with a tail indicating direction of movement).

Any assistance would be greatly appreciated!!!

Did you check what measurement units the stadimeter is giving you?

How would I check that? Anyone got a quick conversion from yards to nm?

Quote:

Originally Posted by ryuzu

If you're using imperial measurements, the units on the stadimeter dial are yards - not feet... There are 3 feet in a yard.

Oh, and the stadimeter measurement is supposed to be done while the scope is at high magnification (although this would lead to over rather than under reading).

r.

I am using imperial measurements and I would expect that the proper information is being passed from the stadimeter to the PK. I am using high-magnification.

I know one other poster suggested it: can we get a picture of the correct stadimeter alignment? I'm guessing it's something I may be doing incorrectly, as my ranges are usually off by about 1/3rd.

Shrap123 · 03-25-07, 03:24 PM

Ok so assuming I use the table or manually calculate the speed how do I enter it in the TDC?

Deep Six · 03-25-07, 03:28 PM

I concur with the above can Neal or one of the boys post a pic of a correctly aligned stadimeter on target.Neal Vid was awesome but with the screen a little small i was unsure if he was.
A.Aligning the Stadimeter id ON TOP of the target is completely covering the target

B.Aligning the Stadimeter where the Stad was just touching the HIGHEST part of the target i.e the mast head?
I have used both and my aim is still crap!!!....Just want to know what is right for stadimeter range input.

Deep six

03-21-07, 10:51 AM	#1
heartc Samurai Navy Join Date: Dec 2006 Location: Munich Posts: 562 Downloads: 71 Uploads: 0	The Silent Hunter 4 TDC discussion TDC instructional video: http://www.subsim.com/radioroom/showthread.php?t=108689 Well, they almost got it. Almost. They made one small mistake which however has a big negative effect on the usefullness of the position keeper. Take a look at the lower dial of the position keeper. You will notice it displays and updates the GYRO ANGLES (just like the green line on the attack map) but instead it should be the TARGET BEARING. There are two ideas behind the position keeper: It should continuesly update the fire solution, taking ownship movement into account (which it does perfectly), but it should also continuesly provide the target position (via bearing and range). Without a bearing readout, we miss a MAJOR feature of the TDC: iRL and in SHI, you were able to CHECK your fire solution after entering the data by watching whether or not the actual target bearing that you can see through the scope and the TDC bearing readout stayed the same. If those two bearings started to drift apart, you knew your solution was not the best, and the faster they drifted apart, the worse it was and you knew your torps are going to miss. If it stayed the same or differed only slowly, you knew the solution was pretty accurate at least if you fire soon and the range was not too great in the later case (when differing slowly). If the solution was bad, you could easily adjust it by changing target speed, i.e. if the target crosses your periscope bearings faster than your TDC showed, you had to increase target speed for example and vice versa. The funny thing is that actually in the manual of SHIV when you check the TDC description section you will read them describing that possibility of "checking" the accuracy of the solution and INDEED, where we now have the Ship name read out in the header above the two dials, on the pic in the manual there is this readout: "Target 10, 010" and indeed the lower dial also shows the bearing of 010, not GYRO ANGLES as it does now. It baffles me that they changed that and I wonder why. A small work around might be to note the difference between gyro angles and actual bearing and watch out that this difference stays the same, however this is inaccurate, needs you constantly calculating and would work only for a rather short time since the difference must change over time. Otherwise I think the game is in fact awesome. Especially cause I didn't even know if it will run at all since I'm only on 1.8 GHz, 512 RAM and 9800Pro, but in fact it runs better than SHIII for me (time compression way better, loading times shorter, runs fluid with some settings I don't care for anyway turned off and the gfx card tuned for performance in the control panel). But I hope they correct the TDC, because being able to actually check your solution for accuracy before firing was a MAJOR feature iRL and in SHI. Last edited by Gizzmoe; 03-25-07 at 02:13 AM.

03-21-07, 11:31 AM	#3
heartc Samurai Navy Join Date: Dec 2006 Location: Munich Posts: 562 Downloads: 71 Uploads: 0	Holy crap. That might well be right. I'm not sure if I'm with you, but I have some idea and will have to check it out asap. Thanks for providing the image scan! Too bad sims do not come with proper manuals anymore, might have spared me from possibly submitting false claims. If a mod reads this, please go ahead and flag the topic as "Resolved" or something, since my change of the header is only visible inside the thread. Thanks. Last edited by heartc; 03-21-07 at 11:43 AM.

03-24-07, 06:38 AM	#8
ParaB Chief Join Date: May 2005 Location: Germany Posts: 327 Downloads: 16 Uploads: 0	TDC woes One thing that's really driving me crazy is the constant resetting of torpedo settings in the TDC (full manual targetting). I set all forward torps for fast speed, impact detonator, set spread angle and depth. Then I open all torpedo doors. After a short time I hear clicking noises and the detonator has switched back to magnetic, as well as screwing over my angle input. The torpedo depth seems to stay as input. Another annoyance: the tube doors seem to close again each time you choose another tube. In SH3 I could use the 3d-switches to keep the doors open, in SH4 there aren't any anymore... PLEASE, dear devs, fix this.

03-25-07, 01:33 AM	#10
Spectre-63 Medic Join Date: Jun 2003 Location: Boise, ID Posts: 159 Downloads: 42 Uploads: 0	TDC/PK confusion!!! HI all - started a second career today using manual TDC and things did not go nearly as well as I'd hoped. The first thing I noticed was that virtually all of my range estimations (using the stadimiter) were well short of the target's actual range. I think I'm using it correctly: setting the horizontal line in the periscope along the waterline of the target, selecting the correct ID in the recognition manual, bringing up the image splitter/stadimeter, and placing the waterline in the top image on the top-most point in the bottom image. At first I thought I was mis-identifying the targets, but the sampan fishing trawlers couldn't be misidentified because there was only one with the correct number of sails. The other thing I noticed is that, over time, the position keeper appears to get confused as to where the target actually is. The only thing I can think of is that my constant re-configuration of the target info is confusing it?? The lack of a functioning chrono is certainly hurting my speed estimates, but I think I can overcome that. I've got the 'turn off map updates' off, so I'm cross-referencing where the target appears on the map with where the TDC thinks the target is (white X with a tail indicating direction of movement). Any assistance would be greatly appreciated!!!

03-25-07, 03:28 PM	#15
Deep Six Ensign Join Date: Mar 2002 Location: England, Manchester. Posts: 235 Downloads: 104 Uploads: 0	I concur with the above can Neal or one of the boys post a pic of a correctly aligned stadimeter on target.Neal Vid was awesome but with the screen a little small i was unsure if he was. A.Aligning the Stadimeter id ON TOP of the target is completely covering the target B.Aligning the Stadimeter where the Stad was just touching the HIGHEST part of the target i.e the mast head? I have used both and my aim is still crap!!!....Just want to know what is right for stadimeter range input. Deep six __________________

03-21-07, 11:18 AM	#2
elanaiba Ace of the Deep Join Date: Mar 2005 Location: Bucharest, Romania Posts: 1,058 Downloads: 3 Uploads: 3	I'm not sure I get the problem right The arrows superimposed on the lower dial mark the gyro angle for the selected torpedo tube. But the bearing to the target is read on the top of the line. Draw a line between the centers of the upper and lower dials and the intersection with the two dials will give you the AOB (for the top one) and the bearing (bottom one). On a dial, read the "relative" value on the inner ring, and the "absolute" value on the outter ring. See this scan from Norman Friedman's book "Us submarines" through 1945".

03-21-07, 09:43 PM	#4
heartc Samurai Navy Join Date: Dec 2006 Location: Munich Posts: 562 Downloads: 71 Uploads: 0	Nope, I'm afraid my initial observation is indeed right. I just checked it out again in-game. Take a look at the image scan elanaiba provided. What we do have on the position keeper in game are the two lower right hand dials. What we do NOT have is a RELATIVE TARGET BEARING (not TRUE BEARING) readout, something similar to what you see on the right hand side in the upper half of the image - actually a numerical readout where it says "Bearing Degrees". We need a TDC output for relative target bearing so that we can compare relative (sighted) target bearing with computed relative target bearing. When you look at the image scan again, you can even see a "Bearing Error" readout which assisted in determining the solution error. We don't neccessarily need this since it would be redundant, but sure enough for the position keeper we need a RELATIVE target bearing output. Hasn't anybody else noticed this or am I really missing something here? SHI had it, too, as a numerical readout similar to the one in the image. In fact I think what elanaiba said might indeed be right, I will check again some time later, but then it is a VERY arkward and highly inaccurate (since hard to read) way for the game to provide relative target bearing, especially when we are talking about small deviations between sighted and computed relative bearing which is the nature of the whole checking technique.

03-21-07, 09:48 PM	#5
Arrowhead2k1 Torpedoman Join Date: Apr 2002 Posts: 112 Downloads: 22 Uploads: 0	You're absolutely right. It would be awesome to have a way to check your solution without having to fire a shot aswell.

03-21-07, 10:02 PM	#6
nattydread Captain Join Date: Jan 2004 Posts: 498 Downloads: 2 Uploads: 0	I have to admit, I was concerned there would be some mistakes going from the U-boat TDC to the US TDC, being that SHIV seemed more or a less a re-dressing of SHIII. I hope they resolve it soon. Things like this makes the difficulty in finding the game not so frustrating.

03-24-07, 03:32 PM	#9
divo 637 Watch Join Date: Jun 2005 Posts: 17 Downloads: 11 Uploads: 0	The original poster is correct. This is not working correctly. The issue is that it will work correctly sometimes then stops working. The PK should mimic a LOS diagram. So that own ship will not always point straight up. The Own Ship ring (the bottom one) should point to the true bearing to the target at the top. And the target ring should point to the true bearing of your ship (so 180 deg out from where own ship ring points). The bug somehow forces a relative bearing of 0 to the top of the ring. Watch the training video that is a sticky. It works fine at the TBT and when he goes below to the scope it works fine for a few seconds then it abruptly jumps to the realative bearing of zero at the top of the ring and does not change on the next several updates. You have to be looking for it. It happend quite fast. This may have something to do with the inputs to the PK so that UbI had designed in some criteria on the way this work (maybe something about bearing inputs). Not sure. but this needs to be fixed.

03-25-07, 03:24 PM	#14
Shrap123 Swabbie Join Date: Feb 2004 Posts: 9 Downloads: 3 Uploads: 0	Ok so assuming I use the table or manually calculate the speed how do I enter it in the TDC?