[TEC] Periscope fields of view - SH4 vs SH3

[panthercules]

Just been toying around, testing a few things out with my current RFB 1.26 install, and I started wondering if the ships really looked right in the scopes - just something gnawing at me about the sizes not looking quite "right" (compared to my memories of how they looked in SH3 anyway), so I decided to do some tests>

I set up a couple of simple missions in SH4 and SH3, each using a British Liberty cargo positioned as close to 1,000 yards away from my sub as I could get it (this was my first try playing with the mission editor in either sim - lost my first German sub to gunfire from the Liberty ship, after which I figured out how to start my u-boat at periscope depth :oops: ). Anyway, as you can see from the series of screenshots below, something odd does seem to be going on with the ship images in SH4 (w/RFB 1.26) compared to SH3:

SH4 Attack Scope at 6X:

http://i3.photobucket.com/albums/y96/Cladean/01_SH4AttackScope6x.jpg

SH3 Attack Scope at 6X:

http://i3.photobucket.com/albums/y96/Cladean/02_SH3Attackscope6x.jpg

SH4 Attack Scope at 1.5X:

http://i3.photobucket.com/albums/y96/Cladean/03_SH4AttackScope1.jpg

SH3 Attack Scope at 1.5X:

http://i3.photobucket.com/albums/y96/Cladean/04_SH3AtackScope1.jpg

As you can see, at 6X magnification the ship almost exactly fills up the scope view screen in SH4, but way more than fills up the view screen in SH3 (so, the ship "looks" larger at 6X in SH3 than in SH4). BUT, at 1.5X, the situation is reversed - in SH3, the ship spans about 40 degrees (based on the bearing scale at top), but in SH4 the ship spans about 60 degrees (so, the ship "looks" larger at 1.5X in SH4 than in SH3).

Is there any reason for this to be occurring, or is this an indication that something is "wrong" with the scope view implementation in SH4 (or SH3 maybe)? NOTE - as it turns out, I'm running RFB 1.26 with the "Betterscopes 1.2 Worn" mod on top of it, (and GWX Expansion on my SH3 install) so maybe it's something related to that particular setup - if I get time tomorrow I may try this with the stock versions and see what happens. Just wondering if anybody else has seen any anomalies like this with their setup.

[Mav87th]

http://www.subsim.com/radioroom/showthread.php?t=115525

Try that thread. I think this is what your looking for :ping:

[panthercules]

http://www.subsim.com/radioroom/showthread.php?t=115525

Try that thread. I think this is what your looking for :ping:

Thanks for the tip - unfortunately, I tried those settings and I got the same results as before (and I did move the "copy of" file that minitweaker makes out of the SH4 folders onto my desktop, so hopefully the game wouldn't try to use the old settings still) with the attack periscope. Also, another odd thing is the the view in the obs scope is now essentially the same as in the attack scope (see pictures below):

Obs scope at 4X:

http://i3.photobucket.com/albums/y96/Cladean/SH4ObsScope4x.jpg

Obs Scope at 1X:

http://i3.photobucket.com/albums/y96/Cladean/SH4ObsScope1x.jpg

I would have thought that the image in the Obs scope should be smaller, given the weaker magnification it should have compared to the attack scope. Wonder what's going on here? - guess I'll try some different tweak numbers and see what happens.

[panthercules]

Hmmmm - curiouser and curiouser. :hmm:

I tried changing the obs scope min/max zoom numbers to .5 and 2, thinking that would make the image smaller - but no change. Then I tried boosting them to 2/10, but again, no change. (and this time, I just deleted the old "copy of" files that minitweaker made). I don't get it.

I guess I'll drop back to the stock cameras.dat and see what that does. :damn:

[panthercules]

Ok - dropping back to stock cameras.dat fixed at least part of the issue - the obs scope images now appear to be suitably smaller than the attack scope images - see screenshots below:

SH4 attack scope at 1.5X:

http://i3.photobucket.com/albums/y96/Cladean/SH4attackscopestock1.jpg

SH4 obs scope at 1.0X:

http://i3.photobucket.com/albums/y96/Cladean/SH4obsscopestock1x.jpg

SH4 attack scope at 6X:

http://i3.photobucket.com/albums/y96/Cladean/SH4attackscopestock6x.jpg

SH4 obs scope at 4X:

http://i3.photobucket.com/albums/y96/Cladean/SH4obsscopestock4x.jpg

It's a start anyway :)

[edit] it's still exhibiting the oddity that in the attack scope the image looks bigger in SH4 (than in SH3) at 1.5X but smaller in SH4 (than in SH3) at 6X. In the obs scope, the image looks bigger in SH4 at 1X and at 4X. Very strange. Oh well - at least the obs scope is back to looking more "right" compared to the attack scope - guess I'll just have to forget how they used to look in SH3 and get used to how they look in SH4. After staring through those SH3 scopes for a couple of years, I was hoping I wouldn't have to recalibrate my eyes to be able to guesstimate ranges in SH4, but unless someone can tell me why changing the zoom numbers doesn't seem to work and how to make the ship images a little smaller (which, now that I think about it, doesn't sound like that great an idea anyway), looks like I'll have to just re-train my eyes.

[Mav87th]

What your looking for is AngularAngle. If that does not match an 8deg FOV lens at the correct zoom level you wont get squad from changing zoom.

Try to install my camaras.dat file and see how that works.

[panthercules]

What your looking for is AngularAngle. If that does not match an 8deg FOV lens at the correct zoom level you wont get squad from changing zoom.

Try to install my camaras.dat file and see how that works.

Well, I tried that but no joy. As you will note from the screenshots below, the ship is back to looking as big or bigger in the Obs scope than it does in the attack scope - that just doesn't seem right to me given the lower magnification the obs scope is supposed to have:

Obs scope at 1x with Mav's camera.dat:

http://i3.photobucket.com/albums/y96/Cladean/SH4Mavobsscope1x.jpg

Attack scope at 1.5x with Mav's camera.dat:

http://i3.photobucket.com/albums/y96/Cladean/SH4Mavattackscope1.jpg

Obs scope at 4x with Mav's camera.dat:

http://i3.photobucket.com/albums/y96/Cladean/SH4Mavobsscope4x.jpg

Attack scope at 6x with Mav's camera.dat:

http://i3.photobucket.com/albums/y96/Cladean/SH4Mavattackscope6x.jpg

Not sure what's going on here, but I guess it's back to stock camera.dat for me at this point unless someone has some other suggestions.

[Mav87th]

Too mee it looks like you have botched the installation of the Better Scopes - perhaps having them switched around.

Appart from that - there is no x1 or x4 zoom in my mod.

The observation scope and the attack scope both had x1,5 and x6 as zoom's. This is reflected in my mod. Further the binocular and the TBT both have x7 in zoom.

The reason that the ships are slightly larger in the observation scope is that the scope image (the hole you look out of) is slightly larger. Thus the angularangle needs to be adjusted acordingly so the ships present them selfs correctly at any given range.

no matter what the ticks in the scope should cover X amount of feet at Y range. This is measured in both degrees (angular field of view) and in feet (linieer field of view). Both scopes have a angular field of view of 8 deg. at high power (x6) and 32 deg. in low power (x1,5)

For example, in hight power with 8 deg. (angular) field of view has a (linear) field of view of 419,4 feet per 1000 yards. Meening a target of 420 ft. in lenght placed at a range of 1000 yards should touch both the left and right side of the periscope view.

As long as the FOV is less than about 10 degrees or so, the following approximation formulas allow one to convert between linear and angular field of view.
Let A be the angular field of view in degrees. Let L be the linear field of view in feet per 1000 yards. Let M be the linear field of view in millimeters per meter. Then:

http://upload.wikimedia.org/math/4/f/7/4f775bcf2dc1995c1fc639749001350b.png
http://upload.wikimedia.org/math/8/e/1/8e10fb88671c9b6145b5daadbb42fb26.png
http://upload.wikimedia.org/math/3/1/3/3130070f8c0ab46b5082cb431fda4a6f.png
http://upload.wikimedia.org/math/2/d/4/2d484bd43ee1d290f0ebef4085b75e90.png "

[panthercules]

Thanks for the explanation - I was basing my labels of 1x/4x and 1.5x/6x on info I had seen online as far as what magnification levels the US scopes had, not what was stated in the mods - I'll have to recheck that research to see if it was wrong or I mis-remembered it (either of which is quite possible).

I sort of understand what you're saying about the angular settings and FOV and touching edges of scopes view etc., but even taking that into account as best I can at this point, it still seems counterintuitive that any image of a ship at a lower magnification would look bigger than the image of the same ship at a higher magnification - this may be something like the binocular view issue, where you know that things don't really look like that (sideways figure eight shape) when you actually look through a real pair of binoculars, but TV, movies and games have used that shape view mask for so long that it feels more natural/right to see it represented that way in game than it would if it were more circular.

At any rate, I've loaded up RFB 1.28 which I believe has your camera.dat settings and stuff in it, so I'll try that without any further tweaks and see how things look.

[Mav87th]

You are absolutely right about the "thing" should look bigger in HIGH power then it will in low power.

High power being x6 in any US scope durring WWII and x1.5 being low power.

A simple source would be the Submarine manual for periscopes.
http://www.maritime.org/fleetsub/pscope/index.htm

4 different scopes are mentioned in it.

Have fun :up:

[panthercules]

Intriguing link - that manual clearly indicates that at least those particular US scopes used the same magnification levels (1.5x and 6x) for both the attack scope and the obs/night scope. I really thought I had seen somewhere that the US used the same approach as the Germans did (reducing magnification) to get more light into their obs/night scope, but from that manual it looks like they didn't. I'll have to see if I can find what I'd found before that made me think that.

Of course, if the magnification levels are the same it would make more sense for the images in the obs scope not to be smaller than the attack scope, like I was thinking they should be. One thing that was weird - from that manual, it looked like it was actually the attack scope that was able to tilt higher and look for planes, and not the obs scope (like it was in the German scopes, apparently) - that would actually seem to make more sense, given that the obs/night scope would be used at night (when planes would be less likely to be up there to spot) and the attack scope (being smaller) would leave less of a wake and be less likely to be spotted by the planes you were trying to spot with it.

I understand that the betterscopes mod is supposed to make the images through the attack scope darker to simulate the obs/night scope letting in more light. Does the game model a higher chance for detection when using the obs/night scope? Does your camera mod reduce the vertical elevation/visibility of the obs scope so you can't really use it to scan the skies as well, and increase it for the attack scope? It seems like given the differences in US scope implementation, it should call for some changes in the way we use these scopes in game, compared to what we got used to in SH3.

[Mav87th]

As I read the manual the observation scope had the highest tilt angle, but the attack scope were allso able to tilt quite a bit.

[panthercules]

As I read the manual the observation scope had the highest tilt angle, but the attack scope were allso able to tilt quite a bit.

Well, I'm not completely sure if I was reading it right, 'cause I'm not sure about what that middle one ( 92KA40T/1.99 PERISCOPE) really was, but the attack one (91KA40T/1.414HA PERISCOPE) had a "High Angle" (HA) designation and gave specs for large max elevation vertical angle of view, whereas the obs/night one (93KN36 PERISCOPE) gave specs for a much lower max elevation angle, from which I based my comments in the earlier post. Interesting reading, though a bit technical - I may give it another go later this week.

[elanaiba]

http://rapidshare.com/files/35332490/Cameras.dat.html

Try this cameras.dat file and let me know how the ships look through the scopes :)

[CaptainCox]

NOT FAIR!!!!! Dev's doing mods now! :lol:



Hahaha way to go man!:up:

[Argus00]

NOT FAIR!!!!! Dev's doing mods now! :lol:



Hahaha way to go man!:up:


lol - maybe they'll turn out a Grey Wolves XP instead of a patch :rotfl:

[tater]

Does the observation scope have a larger objective, but the same magnification in RL? Light gathering is a function of objective diameter (so is angular resolution, actually).

[panthercules]

Does the observation scope have a larger objective, but the same magnification in RL? Light gathering is a function of objective diameter (so is angular resolution, actually).

I believe so - in the manual cited at the link above, the scope which appears to be an attack scope (designated 91KA40T/1.414HA ) is listed as having an "outer diameter of reduced section" (I think that meants the very top/tip of the scope) of 1.414 inches, whereas the scope which appears to be an obs/night scope (designated 93KN36) is listed as having an "Minimum outer diameter of taper section" (which, again, I believe means the very tip/top of the scope shaft) of 3.75", but it lists both scopes having the same 1.5X/6X magnifications, which I take to mean that the night scope uses a bigger opening rather than a lower magnification in order to achieve the better light-gathering capability for night use.

[panthercules]

http://rapidshare.com/files/35332490/Cameras.dat.html

Try this cameras.dat file and let me know how the ships look through the scopes :)

I took a quick look at this, but couldn't tell much difference yet - as it turns out, apparently I trashed my single mission test files when I went back to a stock install for the RFB 1.28 update :cry: so I just took a quick look in the sub school navigation mission (don't have time tonight to rebuild my test missions). I did notice (for the first time) that the obs scope opening is clipped a bit at top and bottom like some other posters mentioned - hard to believe I missed that in my earlier tests, but when I went back to look at those earlier screenshots sure enough it's cropped/clipped in those shots. I wonder how you fix that, as it would be nice to have a full circle in view (though that probably means you'd have to reduce the attack scope view circle size somewhat as well, or else they'll both be the same size again).

I'll take a closer look at it tomorrow when I can recreate my scope test mission, and also take a look at the tweak file values and see what changed in this one.

Thanks for posting it for us to play with :up:

[panthercules]

Ok - I re-created my scope test mission, and took a look using the new cameras.dat file posted by elanaiba above - here's what I saw, compared to what I saw before with RFB 1.28 (I reduced the sizes of the new screenshots before I uploaded them to reduce the "bulk" of the post, but the other ones were already uploaded and I didn't have time to re-size and re-upload them - don't let that throw you):

Elanaiba Attack Scope at 6X:

http://i3.photobucket.com/albums/y96/Cladean/SH4DevfileAttackScope6x.jpg

RFB 1.28 Attack Scope at 6X:

http://i3.photobucket.com/albums/y96/Cladean/SH4Mavattackscope6x.jpg

Elanaiba Attack Scope at 1.5X:

http://i3.photobucket.com/albums/y96/Cladean/SH4DevfileAttackScope1.jpg

RFB 1.28 Attack Scope at 1.5X:

http://i3.photobucket.com/albums/y96/Cladean/SH4Mavattackscope1.jpg

Elanaiba Obs Scope at 6X:

http://i3.photobucket.com/albums/y96/Cladean/SH4DevfileObsScope6x.jpg

RFB 1.28 Obs Scope at 6X:

http://i3.photobucket.com/albums/y96/Cladean/SH4Mavobsscope4x.jpg

Elanaiba Obs Scope at 1.5X:

http://i3.photobucket.com/albums/y96/Cladean/SH4DevfileObsScope1.jpg

RFB 1.28 Obs Scope at 1.5X:

http://i3.photobucket.com/albums/y96/Cladean/SH4Mavobsscope1x.jpg

As you can see, the ships look quite a bit smaller in elanaiba's version than in the Mav/RFB 1.28 version, at both 6X and 1.5X. Also note that in elanaiba's version, the ships don't look the same size in the two scopes when both are at 6X looks bigger/covers more ticks in the attack scope than in the obs scope). Not sure what any of that means yet or which one is more "right" (or even, which one I like better) - just reporting what I saw. Will have to think about this some more.

[WolfyBrandon]

I was actually thinking of posting a topic about this at one time. When I use to play a lot of SH3 by looking through the scope I was able to make a very good judgment about the distance of a ship how far I needed to lead shoot the ship to hit it without gathering any information about it. This made SH3 pretty exciting in times where I needed to make quick shot. When it comes to SH4, I can’t hit the broad side of a barn doing that. Also it bugs me SH4 wont allow me to shoot like that with manual targeting option enabled because by turning the scope wont change where the torpedo fires, aim the scope at 030 and fire and the torpedo runs down 000 not 030. I was trying it with manual targeting off and was having a hard time. I took some screenshots of how far away the ship looked in the scope compared it to how far away it looked having the camera right next to my scope in the 3D view and there was a big difference. Can’t find the screenshots I took, but I think I remember the ship looking like it was further away in the scope than it actually was in the 3D view making me over shoot all the time. Maybe the magnification of the scope is SH4 is off? Something I wanted to look into...

Wolfy

[panthercules]

And the winner is.....

Mav/RFB 1.28 :up:

assuming that the data in the manual cited in the previous posts is correct, anyway. According to that data, the total width of the FOV in both the attack scope and the obs/night scope at 6X should be about 420 feet (had to dust off my trigonometry formulas to figure that out - and my friends said I'd never use that math again after I finished school :know: ). Since the length of a Liberty ship is about 441 feet, at 6X the image of the Liberty ship should just barely spill over/outside each side of the scope view - and that's exactly how it looks in the Mav/RFB 1.28 scope 6X screenshots above, whereas the ship in the elanaiba version only takes up maybe 60-70 percent or so of the width of the scope view areas. (It's harder to tell from the screenshots, but at 1.5x the image should take up about 26% of the total width, and the Mav/RFB image does just that whereas the elanaiba image only takes up about 18% or so of the FOV).

So, kudos for Mav for apparently hitting it on the button, and to Beery for including these settings in RFB 1.28. Now, just gotta go out there and re-train my Mark 1 eyeballs to get used to it. Well Done :rock: