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breadcatcher101
09-26-08, 11:45 AM
The manual states that "the TBT only simulates the measuring process by the usage of a moving line index", not going into much detail. I hardly ever used the TBT even back in auto-targeting but I am at a loss as to how it is done in the game.

What exactly is a "moving line index"? I thought it would be a line you would drag to the topmast but I if so I haven't figured out how to use it.

Rockin Robbins
09-26-08, 12:01 PM
While using the TBT you have the same TDC controls available with the periscope.

http://i196.photobucket.com/albums/aa293/RockinRobbins13/Silent%20Hunter%204/Manual%20TDC%20Range/SH4Img14-11-2007_75732_538-1.jpg

Here's the portion of the TDC on the right side of the screen. First you press the lower left button to bring up the range/bearing input section shown. Now with TBT pointed at the target and locked with the "L" key, you press the upper left button. That's the one that is not red.

You'll see your image in the TBT split into 2 superimposed images: the original image which doesn't move and a second partially transparent image, which you can move using your mouse in the TBT window. You want to move the waterline of the movable image down to touch the tallest masthead and left-click.

Then go back to the input portion shown above and press the red "send range/bearing to TDC" button. You've done it! :know:

Only one more thing to do. Take your manual and use it start a campfire or prop up the short leg of a table.

tomoose
09-26-08, 12:09 PM
Breadcatcher;
take the manual and hang it next to your toilet bowl, it'll do more good there.;)

It sounds like you're used to the German range finder as opposed to the U.S. method. The U.S. method utilizes a second image of the target the bottom of which is placed on the top of the original image in order to calculate the range. The principle is the same but instead of using two horizontal lines as in the German method it's two images.

Hope this helps. If not, search under "using the TDC".

:up:

tomoose
09-26-08, 12:10 PM
Aw poop, RR beat me to it.;)

breadcatcher101
09-26-08, 12:59 PM
Thanks, guys. I don't think I locked the TBT onto the target as best as I can recall. I had ran into a Dutch tugboat and decided to use them as a target in a pratice surface attack--they hate that--when I noticed the problem.

It is true, I am more used to the German way, but I am starting to like the PK.

I appreciate you help.

breadcatcher

Munchausen
09-26-08, 04:23 PM
Thanks, guys. I don't think I locked the TBT onto the target as best as I can recall.

You don't necessarily need to lock the TBT. Any time part of your target is in the crosshairs, you can take a range fix. But, if you haven't centered the crosshairs by locking the TBT, torpedo calculations will be made against wherever it was you had your crosshairs at the time you took the fix.

:hmm: I think you do need to be locked, though, to send mast height.

Phaedrus
09-28-08, 08:40 AM
How do I obtain range?


Not very well Breadcatcher... not very well.



This position keeper thing has got the better of me. I miss my old Sh III TDC when I could put a torpedo any where I wanted it...

Rockin Robbins
09-28-08, 06:07 PM
Phaedrus, the American TDC can do everything the German one can, plus some very neat tricks to boot! It's just a matter of adapting to the different machinery and not trying to insist that it work exactly the same way.

And it takes time because many of the things you do with the TDC are automatic. You need to take them out of automatic into manual to think about every step for awhile. It takes time.

But I can promise that learning the American TDC will make you a better U-Boat skipper, just as learning the German TDC will make you a better fleet boat skipper.

breadcatcher101
09-28-08, 09:36 PM
I got it to work, am getting the double image. I think the first time I didn't click it on or something. I use the scope anyhow. I can get a closer and don't have to be concerned about a shell hitting the boat.

Rockin Robbins
09-29-08, 05:42 AM
http://i196.photobucket.com/albums/aa293/RockinRobbins13/smileys/thumbsup_weird.gif

Hitman
09-29-08, 07:02 AM
Phaedrus, the American TDC can do everything the German one can, plus some very neat tricks to boot!

Except autoupdate with the current bearing of your optics in real time (You must continuously send bearing and range to update the current real position of the target, not the one predicted by the Position Keeper. Although if you have a good solution of course both will match and there is no need to autoupdate). I think that is what Phaedrus was missing and it is specially useful, specially when attacking several targets at a time. In the real US TDC that was solved becaiuse the instrument autoupdated for various targets at a time when told to do so, but in the game you can't :damn:

Rockin Robbins
09-29-08, 11:38 AM
Phaedrus, the American TDC can do everything the German one can, plus some very neat tricks to boot!
Except autoupdate with the current bearing of your optics in real time (You must continuously send bearing and range to update the current real position of the target

But as a result, you can save your own skin by being able to look around without killing your solution. Or, as in the Dick O'Kane technique, you can set up your attack, then look for the present position of the target without worrying about your chosen attack bearing being ruined by moving the scope. The PK is off and you are using the characteristic of the American TDC as a feature, not a defect.:up:

It's all in your mental attitude toward the equipment you are using.

I agree that having the TDC track more than one target at a time would be an improvement in the game. The real American TDC also had an input for target length and calculated offsets for any desired percentage of spread. Both of these were real advantages of the American TDC over the German one and are not modeled in SH4. Neither is a deal killer for either side. Learn both thoroughly and be better at both!

Nisgeis
09-29-08, 01:26 PM
The real American TDC also had an input for target length and calculated offsets for any desired percentage of spread.

RR, where did you read about the TDC calculating offsets, I'd be interested to have a look at it. My understanding of it was something slightly different.

Hitman
09-29-08, 02:34 PM
But as a result, you can save your own skin by being able to look around without killing your solution

In the german TDC you also can. The Kaleun ordered "Lage folgend" or "Lage nicht folgend" and by switching a knob the TDC was un-linked from the optics allowing to take that look around (A blue lamp indicated the unlinked to optics status).

Or, as in the Dick O'Kane technique, you can set up your attack, then look for the present position of the target without worrying about your chosen attack bearing being ruined by moving the scope

You can also do that with the german TDC. Set up the solution, aim the optics and then unlink the TDC so that the optics are free to rotate and the solution is fixed at the point of aim previously chosen.

The real American TDC also had an input for target length and calculated offsets for any desired percentage of spread

The german TDC also had that :) You can see the dial for " Gegner Länge" (Enemy length) here (Highlighted in pink):

http://img244.imageshack.us/img244/6756/82751353bs2.th.jpg (http://img244.imageshack.us/my.php?image=82751353bs2.jpg)


It's all in your mental attitude toward the equipment you are using

Yes to a big extent, but not completely. The american TDC was superior to the german TDC, not because the german was bad, but because the american was the state of the art in those years. The germans created deliberately a simplified TDC to help more novice sailors and IWOs get used to it quickly, so they could pour out new crews faster. Also, because the whole attacking party in the submarine was more reduced (Space limitations) and a simplification of the tasks was highly desirable.

The beauty of the american TDC was the incredible accurancy it could provide, thanks to the position keeper and the ability to directly enter ranges determined with active sonar and radar. This wonderful machine was developed in a time when the doctrine thought that getting close to a target would be very difficult due to enemy ASDIC and low submerged speed in submarines, and it came as a response allowing deadly accurate shots from 4000+ yards :rock:

German doctrine called for close combat action in night surface attack, and hence their TDC was more simplified and with a higher priority in being able to quickly switch between targets, leaving precision in a second row due to the short distance the attack would be done.

Our main problem is not just the attitude as you point out, but the fact that recreating such a complex tool as the US TDC would be a game in itself, and unfortunately the simplified version we have in the game lacks many key features like the spreads based on target length you mentioned. I have solved that with a printed table for various target lengths and distances, but still it would have been awesome to have it calculated in game by the TDC :ping:

Hitman
09-29-08, 02:38 PM
BTW I forgot in all my previous messages to mention that the TBT didn't have any split prism rangefinder AFAIK :hmm:

It just had a graded reticle like the scopes, and when radar ranges where not available, the IWO called the marks to the assitant, who would use a wiz-wheel or a precomputed table to tell the distance.

Rockin Robbins
09-29-08, 04:32 PM
BTW I forgot in all my previous messages to mention that the TBT didn't have any split prism rangefinder AFAIK :hmm:

It just had a graded reticle like the scopes, and when radar ranges where not available, the IWO called the marks to the assitant, who would use a wiz-wheel or a precomputed table to tell the distance.
I forgot about that. You're absolutely right. In fact the first TBTs were just a stand with a mount for standard binoculars and only sent bearing. Later ones had permanently mounted binoculars but no mechanism for stadimeter. Their ranges came from radar and were much better anyway. Unfortunately, there too, we have no range input from radar to TDC as the subs did after 1944.

Working with the German TDC is to realize that it was an entirely different proposition than the American piece of awesome complexity. Where we used incredibly complex machinery, the Germans used simpler ingenuity. Just check out the OLC GUI in SH3 and you have to just shake your head in wonder. What we did with brute force and a million pieces, the Germans seemed to do without a wasted part and by continually simplifying the process. It makes you wonder why they chose the opposite strategy with their Panzer tanks' over-complex designs.

My first attacks in the German U-Boat were Dick O'Kane attacks with the periscope unhitched from the TDC and they were deadly because they were indentical to those I make in the Kraken except that the measurements were metric. The metric explosions seemed just as satisfying as the imperial ones.:rock:

In practice, on a surface attack without radar, there would be a man on periscope watch below to take range measurements if he could. The effect would be the same as our TDC with stadimeter, so I don't think the game suffers too badly from having one of those cursed things where it doesn't belong.:rotfl:

Where's that diagram of the American TDC......
http://i196.photobucket.com/albums/aa293/RockinRobbins13/Silent%20Hunter%204/Sub%20Manual%20Stuff/PKandSoundBearingConverterdiagram.jpg

There's the target length input crank on the bottom. Notice the distance to track output near the top? All kinds of things in both American and German TDC's that aren't modeled!

Here's a neat one. I bet you figured out already that with prop torque the reach and turning radius of a torpedo could be different, depending on whether it was turning left or right. Oh? Didn't think of that one? The TDC designers did and the TDC was adjustable out of the box to account for any parameters of newly acquired torpedoes:

http://i196.photobucket.com/albums/aa293/RockinRobbins13/Silent%20Hunter%204/Sub%20Manual%20Stuff/TorpedoReachTurningRadiusAdjustment.jpg

Freaky, eh? All you modders with compulsive tweaking disorder would have been in heaven aboard a submarine.

http://i196.photobucket.com/albums/aa293/RockinRobbins13/Silent%20Hunter%204/Sub%20Manual%20Stuff/HandInputs1.jpg
.......................................... http://i196.photobucket.com/albums/aa293/RockinRobbins13/Silent%20Hunter%204/Sub%20Manual%20Stuff/HandInputs2.jpg

A list of all hand inputs into the American TDC. When you consider that both German and American TDCs were nothing less than mechanical computers, you have to be amazed and wonder if such feats would even be conceivable today.