Type VII periscopes - field of view

[XenonSurf]

Hi,

From the information I was able to gather, the observation periscope in type VII u-boats were harder to detect compared to attack periscopes and they had a better angle elevation capability also. But what about the field of view? Was it smaller or larger?
When I look at the different scope mods for SH5 it seems to me that there is more fantasy from the modders involved rather than accurate scope representation. Sure, a computer screen cannot truly reflect what you would see in real life ...
So, to my taste, the Manos scope has the most ugly observation scope I have ever seen, I can't imagine that the real thing would cut the view like that above and below (or is this a scale error, and the Manos scope was not designed for 16:9?), then the 'Large Optics for TDW scopes' seem to me very high-tech, they rather act like an external camera instead of a scope :)

Between these 2 extremes, there is a scope I like, it's not so 'tech' but should come close to the real thing: the 'emtguf_rework_scopes' which is an optional part of the TDW NewUIs 7_5_0 that I would like to use in my modlist for a smaller field of view, but again: which of the 2 installed scopes in the sub had a smaller field of view, or wasn't there any difference?


Thanks,
XS

[bstanko6]

The obs scope allows for sky searches. My attack scope has a filter to simulate less light.

[XenonSurf]

The obs scope allows for sky searches. My attack scope has a filter to simulate less light.


Well, in this case emtguf_rework_scopes are very good indeed, the attack scope has lower light and a 'apparent' smaller view, very difficult to mod considered that there is only 1 camera file to work with.

So, the real attack persiscope is the smaller one by horizontal coverage?

[Sailor Steve]

First, it's the Attack Periscope that's harder to detect.

Observation periscope plate from captured U-570 (renamed HMS Graph):

Maximum diameter = 7.1 inches.
Maximum diameter of head = 4 inches.

1.5x = 38 degrees
6X = 9 degrees (US source)

1.54x = 36.38 degrees
6.1x = 8.46 degrees

Exit pupil = 7 mm

Attack periscope:

1.5x = 38 degrees
6x = 9 degrees

Exit pupil = 3.5 mm

Prism tilts from -15 to +20 degrees

Direct reading range scale

includes ray filters

Well-illuminated azimuth with vernier and bearing marker

http://www.uboatarchive.net/U-570/U-570ONIReport.htm
http://www.uboatarchive.net/U-570/U-570BritishReport.htm

[Aktungbby]

http://www.uboatarchive.net/U-570/U-570ONIReportPgg34a.jpgFROM THE BRITISH REPORT OF THE CAPTURED U-570 P ATTACK PERISCOPE The "attack" periscope was definitely the most impressive installation in the ship. It has elicited the greatest admiration from both British submarine officers and the observers. It is described by experienced submarine commanders as "the answer to an attack officer's prayer". This "fixed-height-of-eye" periscope is beautifully engineered.... All officers with whom this periscope were discussed agreed that it is the best built and most satisfactory periscope from a military point of view that they had ever seen, and they considered that the concessions in space and weight to accommodate it were fully justified. It is recommended that full constructional details of this instrument be obtained from the Admiralty, and that the manufacture of a U.S. prototype to this design be put in hand at the earliest possible date. The small size of the top of the periscope itself, the small minimum diameter of the tapered section, and the spirally wound wire on the lower part of the tapered section should be noted. A sketch of the upper end of this periscope is bound herein. The apparent purpose of the wire spirally wound on the periscope is the reduction of periscope wake. Early test of the effectiveness of this device is recommended. :Kaleun_Periskop:A REAL 'EYE OPENER' INDEED

[XenonSurf]

That's brilliant information, thank you very much Sailor Steve and Aktungbby :up:

Still going through this valuable data. I can see more clearly the tactical advantages of the 2 scopes, as I imagine it was especially important to avoid visual detection of the scope prior of an attack in order to not anulate the TDC and firing solutions gathered. So the scope constructors have at least made any possible effort to realize this.

[bstanko6]

It was not uncommon for both the commander and XO to use both scopes. But only at distance or at night to confirm TDC data as they make the attack run.

You see this in action in UBOAT. Which is a cool thing!

[Sailor Steve]

One thing that gets left out of the games is the vibration problem. The sub has to be travelling at three knots or less, not only to reduce the wake that makes the boat visible to surface ships, but also because above that the 'scope begins to vibrate so badly that it becomes impossible to see.

[XenonSurf]

One thing that gets left out of the games is the vibration problem. The sub has to be travelling at three knots or less, not only to reduce the wake that makes the boat visible to surface ships, but also because above that the 'scope begins to vibrate so badly that it becomes impossible to see.


I wait until I'm under 2 knots to use any scope (in SH, AOD etc.), not because of your interesting reason (good to know, thank you), but to avoid the water trail that could track my sub in calm sea situations, although this is surely exagerated and not considered in any sub game, if yes then in SH1 or AOD which have excellent AI routines.
I also have the idea that a scope could get severely damaged if used above a certain speed, I think about 5 knots, but that's probably not a factor either.