is this a problem - one degree out?

fw66 · 05-14-10, 08:26 AM

I'm not able to check whether this happens on my game atm, but do you use a higher resolution than the original 1024x768 (or whatever it is)? that may cause this issue.

Anyway, it shouldn't affect targeting unless you specifically use that image to aid your calculations, and it would only be out by one degree anyway, so shouldn't really make a difference if you're close.

Pisces · 05-14-10, 08:38 AM

One degree is 17.5 meters wide at 1000m distance. Since the bearing tool has a 1.5km radius you'll find you're 26 meters of from where you think it is. But that's not so bad because all plot's are off by one degree. And as was already said, at these distances, the target is usually much bigger than that one degree.

It should not be too difficult to correct the image with a 'photoshop' program by counter rotating the image 1 degree. But that probably would make it more blurry.

flag4 · 05-14-10, 09:07 AM

Quote:

Originally Posted by fw66

I'm not able to check whether this happens on my game atm, but do you use a higher resolution than the original 1024x768 (or whatever it is)? that may cause this issue.

Anyway, it shouldn't affect targeting unless you specifically use that image to aid your calculations, and it would only be out by one degree anyway, so shouldn't really make a difference if you're close.

Quote:

Originally Posted by Pisces

One degree is 17.5 meters wide at 1000m distance. Since the bearing tool has a 1.5km radius you'll find you're 26 meters of from where you think it is. But that's not so bad because all plot's are off by one degree. And as was already said, at these distances, the target is usually much bigger than that one degree.

It should not be too difficult to correct the image with a 'photoshop' program by counter rotating the image 1 degree. But that probably would make it more blurry.

thanks guys: fw66 - you are streets ahead of me. i have no idea what res. my screen is set at!

Pisces: it amazes me how good some of the Kaleuns - like yourself, are at maths, working stuff out. when you put it that way it seems like a great deal - 26 meters!! maybe it does not affect game play after all. and thanks again!

Hook · 05-14-10, 03:50 PM

There are actually two problems. The first is that the overlay is about 1/2 degree off, apparently intentionally. The second is that the game will center the rudder as soon as your ship is within one degree of the intended course.

It's easy enough to fix the overlay problem in photoshop. Just edit the alpha channel and perform an arbitrary rotation so that the grid lines up exactly top to bottom. The resolution isn't that good anyway, so you won't lose anything. While you're at it, copy and paste the sub silhouette from the stock game to the center of the grid. You may have to move the entire thing a pixel or two to one side to get everything to line up.

As the boat moves, the heading will drift. You can watch your rudder go 3 degrees to one side or the other, then back again, as corrections are made. The game is pretty good at keeping you within one degree of true course, but you can tell on a long leg that you are off to one side at the end of it. Not much to be done about this except use shorter course legs.

Hook

irish1958 · 05-15-10, 07:48 AM

Quote:

Originally Posted by Hook

There are actually two problems. The first is that the overlay is about 1/2 degree off, apparently intentionally. The second is that the game will center the rudder as soon as your ship is within one degree of the intended course.

It's easy enough to fix the overlay problem in photoshop. Just edit the alpha channel and perform an arbitrary rotation so that the grid lines up exactly top to bottom. The resolution isn't that good anyway, so you won't lose anything. While you're at it, copy and paste the sub silhouette from the stock game to the center of the grid. You may have to move the entire thing a pixel or two to one side to get everything to line up.

As the boat moves, the heading will drift. You can watch your rudder go 3 degrees to one side or the other, then back again, as corrections are made. The game is pretty good at keeping you within one degree of true course, but you can tell on a long leg that you are off to one side at the end of it. Not much to be done about this except use shorter course legs.

Hook

As above. In WWII, GPS with satellite guidance was not available. A lone ship often wandered about until it's course could be corrected.
I think the game does a good job in this.

Hook · 05-15-10, 08:25 AM

If my Prussian helmsman can't keep within 1/2 of a degree of an assigned course, I'll be getting me a new Prussian helmsman. We aren't using the compass from a box of Cracker Jack, you know.

Actually, I don't mind the course being off as much as a degree, but if a plotting tool isn't accurate, I'd rather do without it. Matter of fact, I was in the process of changing back to the stock map symbol without the overlay when I realized what the problems were and figured I'd try fixing them first. Turns out it worked.

Hook

Bosje · 05-15-10, 08:36 AM

happens to me all the time, when i need an accurate plot on the charts i often manually move the boat so that she lines up (almost) perfectly with the course line, that helps to draw a few AOB lines.

even so, after traveling 2 km at silent running at periscope depth, the boat is usually not on that line anymore. as long as you shoot from the periscope, it's not a problem (1 degree aob error has almost no effect, compared to forgetting to open the tube doors for example)

i sort of like the inaccuracy though, as has already been said: it's not like they had GPS back then

Hook · 05-15-10, 09:03 AM

You'll never get accuracy closer than about 1 degree, 1 knot, or a couple of significant digits of range, even if your instrumentation is dead on perfect. The way to introduce inaccuracy is not to skew the instruments but to force you do do more estimation. For example, don't mark every degree on that overlay, just every 5 degrees.

There's a similar situation with the bearing in the binoculars. There's no index line, so you can't estimate a bearing closer than about 5 degrees. The bearing scale in the binoculars is there for situational awareness, not to allow you to measure bearings. If you want to make it even less accurate, remove all markings except every 20 degrees. Your accuracy will still be about 5 degrees though.

Hook

05-14-10, 08:38 AM	#2
Pisces Silent Hunter Join Date: Dec 2004 Location: AN9771 Posts: 4,904 Downloads: 304 Uploads: 0	One degree is 17.5 meters wide at 1000m distance. Since the bearing tool has a 1.5km radius you'll find you're 26 meters of from where you think it is. But that's not so bad because all plot's are off by one degree. And as was already said, at these distances, the target is usually much bigger than that one degree. It should not be too difficult to correct the image with a 'photoshop' program by counter rotating the image 1 degree. But that probably would make it more blurry. __________________ My site downloads: https://ricojansen.nl/downloads

05-15-10, 08:36 AM	#7
Bosje Seasoned Skipper Join Date: Apr 2008 Posts: 732 Downloads: 89 Uploads: 0	happens to me all the time, when i need an accurate plot on the charts i often manually move the boat so that she lines up (almost) perfectly with the course line, that helps to draw a few AOB lines. even so, after traveling 2 km at silent running at periscope depth, the boat is usually not on that line anymore. as long as you shoot from the periscope, it's not a problem (1 degree aob error has almost no effect, compared to forgetting to open the tube doors for example) i sort of like the inaccuracy though, as has already been said: it's not like they had GPS back then __________________ And when an 800-ton Uboat has you by the tits... you listen!

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05-14-10, 08:26 AM	#1
fw66 Torpedoman Join Date: Apr 2008 Location: UK Posts: 119 Downloads: 53 Uploads: 0	I'm not able to check whether this happens on my game atm, but do you use a higher resolution than the original 1024x768 (or whatever it is)? that may cause this issue. Anyway, it shouldn't affect targeting unless you specifically use that image to aid your calculations, and it would only be out by one degree anyway, so shouldn't really make a difference if you're close.

05-14-10, 03:50 PM	#4
Hook Bosun Join Date: Apr 2002 Posts: 63 Downloads: 10 Uploads: 0	There are actually two problems. The first is that the overlay is about 1/2 degree off, apparently intentionally. The second is that the game will center the rudder as soon as your ship is within one degree of the intended course. It's easy enough to fix the overlay problem in photoshop. Just edit the alpha channel and perform an arbitrary rotation so that the grid lines up exactly top to bottom. The resolution isn't that good anyway, so you won't lose anything. While you're at it, copy and paste the sub silhouette from the stock game to the center of the grid. You may have to move the entire thing a pixel or two to one side to get everything to line up. As the boat moves, the heading will drift. You can watch your rudder go 3 degrees to one side or the other, then back again, as corrections are made. The game is pretty good at keeping you within one degree of true course, but you can tell on a long leg that you are off to one side at the end of it. Not much to be done about this except use shorter course legs. Hook

05-15-10, 08:25 AM	#6
Hook Bosun Join Date: Apr 2002 Posts: 63 Downloads: 10 Uploads: 0	If my Prussian helmsman can't keep within 1/2 of a degree of an assigned course, I'll be getting me a new Prussian helmsman. We aren't using the compass from a box of Cracker Jack, you know. Actually, I don't mind the course being off as much as a degree, but if a plotting tool isn't accurate, I'd rather do without it. Matter of fact, I was in the process of changing back to the stock map symbol without the overlay when I realized what the problems were and figured I'd try fixing them first. Turns out it worked. Hook

05-15-10, 09:03 AM	#8
Hook Bosun Join Date: Apr 2002 Posts: 63 Downloads: 10 Uploads: 0	You'll never get accuracy closer than about 1 degree, 1 knot, or a couple of significant digits of range, even if your instrumentation is dead on perfect. The way to introduce inaccuracy is not to skew the instruments but to force you do do more estimation. For example, don't mark every degree on that overlay, just every 5 degrees. There's a similar situation with the bearing in the binoculars. There's no index line, so you can't estimate a bearing closer than about 5 degrees. The bearing scale in the binoculars is there for situational awareness, not to allow you to measure bearings. If you want to make it even less accurate, remove all markings except every 20 degrees. Your accuracy will still be about 5 degrees though. Hook