Can someone explain stadimeter in detail?

DJSatane · 03-22-07, 09:52 PM

I understand math behind stadimeter(or at least I beleive I do).

What I don't understand is why do we need to put double image, does it help to estimate the angle A better?

I understand that once we have side x distance and angle A, the system uses tan(A) = x/y. This way we can get distance or value of y. But how does exactly stadimeter calculate angle A? Can anyone shed some light on the mechanics behind it?

fullmetaledges · 03-22-07, 11:28 PM

I think the purpose behind the double image is as the range changes so does angle A. They figured an easy and quick way to figure out angle A and put it into the equation would be to superimpose an image and have you line up the mast to the water line. If x=mast height and angle A=the angle between ownship and target mast height and y equals range than. Range= x multiplited by the cotangent of angle A. it's just an easy way to figure out that equation without a pencil and paper, remember they had no calculators

NefariousKoel · 03-23-07, 12:04 AM

Yes, and the other popular way to use a stadimeter is to take a periscope photo and drag one half of it down so the highest mast is level with the waterline. That's great if you have the waterline perfectly lined up.

At least with the offset photo, you can compare it with exactly where you had the scope lined up on it originally. I love it.

DJSatane · 03-23-07, 04:10 AM

thanks.

P_Funk · 03-23-07, 04:34 AM

Quote:

Originally Posted by NefariousKoel

Yes, and the other popular way to use a stadimeter is to take a periscope photo and drag one half of it down so the highest mast is level with the waterline. That's great if you have the waterline perfectly lined up.

At least with the offset photo, you can compare it with exactly where you had the scope lined up on it originally. I love it.

That is indeed one of the few clear advances that SH4 has made. Not very realistic but still neat.

Immacolata · 03-23-07, 05:57 AM

Wasnt it like that on US Subs? I thought I read somewhere that there was a special mirror optics used to create this superimposed mirror image that the periscope operator could manipulate.

P_Funk · 03-23-07, 06:27 AM

Quote:

Originally Posted by Immacolata

Wasnt it like that on US Subs? I thought I read somewhere that there was a special mirror optics used to create this superimposed mirror image that the periscope operator could manipulate.

REALLY?! Okay I take it back. If thats real then that is a major bit of realism that the devs came up with AND its incredibly functional. I say, good show.

Tranton · 03-23-07, 06:39 AM

Quote:

Originally Posted by Immacolata

Wasnt it like that on US Subs? I thought I read somewhere that there was a special mirror optics used to create this superimposed mirror image that the periscope operator could manipulate.

Yeah I think in one of the Dev interviews they mentioned that the stadimeter on a WWII fleet sub operated different than the Nazi one and used a double image.

Nightmare · 03-23-07, 11:10 AM

Yes, that is how the stadimeter functioned in real life. Go to this page on fleetsubmarine.com and scroll down to "periscope controls."

03-22-07, 09:52 PM	#1
DJSatane Electrician's Mate Join Date: Apr 2005 Posts: 140 Downloads: 1 Uploads: 0	Can someone explain stadimeter in detail? I understand math behind stadimeter(or at least I beleive I do). What I don't understand is why do we need to put double image, does it help to estimate the angle A better? I understand that once we have side x distance and angle A, the system uses tan(A) = x/y. This way we can get distance or value of y. But how does exactly stadimeter calculate angle A? Can anyone shed some light on the mechanics behind it? __________________ DJSatane - https://twitter.com/DJSatane

03-23-07, 12:04 AM	#3
NefariousKoel Ace of the Deep Join Date: Nov 2002 Location: No-good Missouri scum Posts: 1,223 Downloads: 43 Uploads: 0	Yes, and the other popular way to use a stadimeter is to take a periscope photo and drag one half of it down so the highest mast is level with the waterline. That's great if you have the waterline perfectly lined up. At least with the offset photo, you can compare it with exactly where you had the scope lined up on it originally. I love it. __________________ "When Gary told me he had found Jesus, I thought, Yahoo! We're rich! But it turned out to be something different." - Jack Handey

03-23-07, 04:10 AM	#4
DJSatane Electrician's Mate Join Date: Apr 2005 Posts: 140 Downloads: 1 Uploads: 0	thanks. __________________ DJSatane - https://twitter.com/DJSatane

03-23-07, 05:57 AM	#6
Immacolata Grey Wolf Join Date: Apr 2005 Posts: 798 Downloads: 3 Uploads: 0	Wasnt it like that on US Subs? I thought I read somewhere that there was a special mirror optics used to create this superimposed mirror image that the periscope operator could manipulate. __________________ "The power of the executive to cast a man into prison without formulating any charge known to the law, and particularly to deny him the judgment of his peers, is in the highest degree odious, and the foundation of all totalitarian government whether Nazi or Communist." - W. Churchill

03-22-07, 11:28 PM	#2
fullmetaledges Chief Join Date: Jul 2006 Location: Utah Posts: 314 Downloads: 120 Uploads: 0	I think the purpose behind the double image is as the range changes so does angle A. They figured an easy and quick way to figure out angle A and put it into the equation would be to superimpose an image and have you line up the mast to the water line. If x=mast height and angle A=the angle between ownship and target mast height and y equals range than. Range= x multiplited by the cotangent of angle A. it's just an easy way to figure out that equation without a pencil and paper, remember they had no calculators

03-23-07, 11:10 AM	#9
Nightmare Engineer Join Date: Nov 2003 Location: Portland, OR Posts: 210 Downloads: 10 Uploads: 0	Yes, that is how the stadimeter functioned in real life. Go to this page on fleetsubmarine.com and scroll down to "periscope controls."