Binocular magnification

[Sag75]

Hi to all,

I saw in Camera.dat binocular has the same magnification of UZO and attack periscope (10x).

What was the true magnification used by binoculars on U-boot?


i.e. increase binoculars mag. to 15x may be more useful to see flag in night or foggy weather..

any comments?

thanks!

[Hitman]

Hi,

the cameras.dat is not always representative of the real zoom you get. There are two values which affect this, the Aperture angle (Also known in english as angular field of view), and the zoom. But you also must take into account a third parameter that we get because we are playing on a computer screen and not looking through real binoculars: The size of the image in yoru screen. Thus it is a bit complicated and you must tweak all of them coherently if you want to have a correct result. I'm taking big care with that in my upcoming interface mod :up:

As for your original question (Sorry for the long previous explanation), the real life values used on Uboats were these:

-Standard watch crew binoculars: 7x (Zeiss 7x50 item)
-Special Commander binoculars: 8x (Zeiss 8x60 item)

7x50 is much better for general scanning and finding objects, specially in an unstable platform like a Uboat bridge. The 8x instead is better to see details once the object has been detected. Hence the commander, who was called to the bridge when the crew had already spotted something, came up with the 8x binoculars to be able to have a better idea of what was out there.

[Sag75]

Thanks for your accurate explanation, I modified the binocular zoom level in camera.dat from 8x to 12x. In game this gives a little more zoom than UZO (10x). I think UZO values are fine because you need the stadimeter in it and you need to see the whole ship in your field to find its height. About binoculars it's different, and putting 12x the visual seems a little more realistic on the monitor to me, and I can get a little better view of the flag at long distances.. that was my purpose..

Anyway, what happens if I change the Aperture angle that is 65 now in camera.dat? And what is the clip distance (1.2m)? (UZO's are 60 and 5.0)


thanks!

[Magic1111]

Hi to all,

I saw in Camera.dat binocular has the same magnification of UZO and attack periscope (10x).

What was the true magnification used by binoculars on U-boot?


i.e. increase binoculars mag. to 15x may be more useful to see flag in night or foggy weather..

any comments?

thanks!

Hello !

Look at this two Links, perhaps it is interesting for you:

http://194.50.68.113/anzeigen/s-Anzeige/Dienstglas-U-Boot-7x50-blc-Zeiss-Fernglas-Kriegsmarine-Binoculars/1359535

https://www.militaria-agent.com/catalog/3RD_REICH_KRIEGSMARINE_BINOCULARS_6X50_e.html

Best regards,
Magic

[Sag75]

thanks! :up:

..And what is the difference between Zoom and Aperture Angle in the game..?

I mean, if I change the zoom value I can get a closer ship, but it happens even if I change the aperture angle.. is there a difference in terms of resolution or night sight in the game when I change either one or the other?

[Hitman]

..And what is the difference between Zoom and Aperture Angle in the game..?

Actually, no real one. In real life optics, the higher the magnification, the lower the aperture (field of view). The main purpose in the game is probably just to calibrate acurately the appearance of the optics. But it won't matter if you use for example an aperture of 7.5 º (Which is more or less what a 7x zoom gives you) or a higher aperture w¡ith the 7x zoom.

What matters is that, once you have decided which size you want the image to have in the screen (I mean the window in which the image seen through the optics is rendered, which doesn't always cover the whole screen), you can first set the zoom level and later adjust the aperture angle to calibrate ita ccurately for the one it should have.

Sorry, it's a bit difficult to explain, but I hope you get it. Set the zoom first, and then tweak the aperture until you see in the window as many degrees as you should expect (F.e. Zeiss 7x50 Uboat binoculars had a field of view of 125 metres @ 1000 metres distance. Put a 125 metres long ship at 1000 metres from you with the mission editor, and check that it covers exactly the whole lense)

Hope that helps :up:

[Sag75]

Thank you very much! it helped a lot..

Before reading your answer I tried some tests and I saw there are not large differences between increasing zoom or decreasing aperture, at least in terms of resolution. I'll try putting a 125m long ship at 1000m and let's see what happens!:up:

[Sag75]

Ok, I didn't find a 125m ship, so I used a maintenance dock that is 130m long. I tested it at 1000m by tweaking binocular zoom at 12x and keeping the defaut 65° in aperture. At 12x the dock was a bit wider than the field.. but I can keep in mind I'm using the 8x60 as Commander of my Uboot!:D


Hitman, could you tell me the formula by which you calculated that a 125m long ship at 1000m stays within the aperture angle?

Or, how would be your example using a 8x60?


thanks!

[Hitman]

The example is using the field of view of a Zeiss 7x50 Uboat binocular, which has a 7.25º aperture.

Aproximately 1000 metres (In fact 982 metres) = 125 / Tangent of 7.25

The problem is that in real life zoom and angle of aperture are different and independent to a certain extent, while in the game they are not.

For an 8x60 Uboat Zeiss binocular, the field of view is 6º, which means that you should place at 1000 metres an object of 105 metres

1000 metres (In fact 999 metres) = 105 / Tangent of 6

:up:

[Sag75]

okay, to have a 8x60 I tweaked binoculars as zoom 12x and aperture 60.0°. In this way using a coal carrier (98 meters long) put at 1000m I was able to see it fitted into the binocular field. Well.. telling the true, it was a little wider, probalby a couple of meters more! But I kept it because on monitor sight it's better have a little zoom more! So I'm now satisfied, at 8500/9000m the flag completely disappeared on UZO, but was still visible at my new 8x60 binocular, even if at that distance it was of course impossible to see the type..

Hitman, are you sure Aperture angle value in game doesn't affect player night visibility? I remember that in SH3 stock.. the manual sayd Observation periscope was able to see better at night than Attack one, and I was (probalby?) able to see this small difference.. but no more in GWX (that both have the same aperture now.... But I don't know the original apertures of stock periscopes..)


..anyway.... that's it! thanks a lot for suggestions!

[Hitman]

Hitman, are you sure Aperture angle value in game doesn't affect player night visibility?

Yes I am, it only modifies the wideness of the image you can see. The confusion comes from an old urban legend I have seen repeated in these and other forums about the observation scope having that larger FOV and also more light transmission. The observation scope had indeed a much better light transmission, but that happened because of the increased size of the lense, not because it had a wider angle of view. In fact, both scopes had the same angle or aperture and magnifications (1.5x and 6x).

This all also happens in binoculars. For example, a 7x50 will always have a much better light transmission than a 7x40, even if they have the same field of view and zoom. The 50 mm lense allows more light to go through than the 40mm, and that's why you will be able to see better in the dark with it.

You can find much more useful info, clearly explained, here: http://www.chuckhawks.com/binocular_basics.htm