[HT] [TS] Night Vision Devices - PNVGs and ANVIS

[General Lee]

Hello everyone,

There is a question gnawing me lately. NVG's in Gurps provides a narrow field of view (~40º), colorblindness and -3 for lack of depth perception. Green Eyes (Tactical Shooting, p.38) negate some of this shortcomings. Moreover, if using the Aiming rule described in Tactical Shooting, one cannot make sighted or aimed shots using NVGs.

I was reading No Easy Day, that describes the Operation Neptune Spear (the killing of OBL), and notice the indication of the use of PNVGs (Panoramic NVGs) with field of view of ~97º, also seen in Zero Dark Hour film (NVGs with four tubes). According to the descriptions of this equipment, the operator have peripheral vision, without needing to maintain his head in a constant swivel (which realistically describes Green Eyes).

Googling it, I also found that PNVGs have an increased depth perception given that the humam brain process the images from two separate sources (each eye). IIRC, the -3 penalty comes from the lack of depth perception, as having the One Eye Disavantage.

So, using binocular NVGs, as PNVGs and ANVIS (Aviation NVGs), would negate or mitigate this shortcomings without need of Green Eyes?

For example, a pilot using an ANVIS would still have Colorblindness and No Peripheral Vision (FoV 40º), but would have no penalty or -1 for vision rolls, instead of -3.

An Operator using a PNVG would still have colorblindness, but retain Peripheral Vision and have no penalty, -1 (as above in ANVIS) or -2 (as Green Eyes).

The disavantages of using such devices are cost and weight.

What are your thoughts on this?

Thanks, in advance.

[malloyd]

Originally Posted by General Lee

So, using binocular NVGs, as PNVGs and ANVIS (Aviation NVGs), would negate or mitigate this shortcomings without need of Green Eyes?

Eventually. With two sensors with the same spacing as your eyes, and two display surfaces covering the full field of vision of each of them, you could indeed totally avoid the depth perception and limited field of view problems. This sounds easy for mature TL9, and perfectly reasonable at TL8 if cost is no object. Whether any *mass produced* TL8 gear comes close enough to do it too is a more open question, but you could probably defend a ruling either way.

Incidentally, while getting used to the depth cues problem seems possible - human vision actually uses quite a lot of strategies other than parallax for that anyway, I'm pretty skeptical of a perk allowing you to mitigate No Peripheral Vision. It begs the question if you can use this scan pattern with the narrow field glasses on and negate the penalty, why can't I buy off the actual disadvantage the same way? I suspect Green Eyes of being a cinematic perk despite where it first appeared.

[Anthony]

Realistically, conventional (40º) NVG isn't No Peripheral Vision [-15], it's Tunnel Vision [-30]. Panoramic NVG is No Peripheral Vision, even 97º is terrible compared to eyes (and it's still only 40º vertical, it's just three overlapping 40º circular zones). A double sensor should eliminate the One Eye penalty, at least within its central field (only the central 40º has double coverage).

Note that, at 64 lp/mm and an 18mm sensor for a 40º field of view per tube, resolution is 40º / (18 * 64) or 2.1 MOA, slightly worse than 20:40 vision.

[General Lee]

Originally Posted by Anthony

Realistically, conventional (40º) NVG isn't No Peripheral Vision [-15], it's Tunnel Vision [-30]. Panoramic NVG is No Peripheral Vision, even 97º is terrible compared to eyes (and it's still only 40º vertical, it's just three overlapping 40º circular zones). A double sensor should eliminate the One Eye penalty, at least within its central field (only the central 40º has double coverage).

Note that, at 64 lp/mm and an 18mm sensor for a 40º field of view per tube, resolution is 40º / (18 * 64) or 2.1 MOA, slightly worse than 20:40 vision.

Reading Basic Set: Characters, p. 151, the definition for Non Peripheral Vision really is FoV 120º and Tunnel Vision FoV 60º. So, using NVGs is worse than described in Tactical Shooting! Any thoughts on this?

Should Green Eyes actually mitigate the effect of Tunnel Vision for Non Peripheral with traditional NVGs (AN/PVS-7, or AN/PVS-14) , and Non Peripheral to Normal with PNVGs?

As for ANVIS, so a pilot using this kind of NVGs would have a visual acuity of 20:40. Did not this represent some minor form of bad sight (nearsighted), only when NVG worn? Or it is below game granularity?

[Ulzgoroth]

Originally Posted by General Lee

Reading Basic Set: Characters, p. 151, the definition for Non Peripheral Vision really is FoV 120º and Tunnel Vision FoV 60º. So, using NVGs is worse than described in Tactical Shooting! Any thoughts on this?

The Basic Set does not assume human characters have their heads clamped in place.

[General Lee]

Originally Posted by malloyd

Eventually. With two sensors with the same spacing as your eyes, and two display surfaces covering the full field of vision of each of them, you could indeed totally avoid the depth perception and limited field of view problems. This sounds easy for mature TL9, and perfectly reasonable at TL8 if cost is no object. Whether any *mass produced* TL8 gear comes close enough to do it too is a more open question, but you could probably defend a ruling either way.

Actually, I think that the tecnology is pretty mature in TL8, but did not permit total visul fidelity between dayligt and night vision. Some night vision devices at european market as Thales's MONIE could be worned as a pair, giving a binocular night vision goggles. IIRC, LUCIE is also an advanced NVG.

In Brazil, NVGs are not regularly worn, only Special Forces and aircraft pilots use it. Even then, a knocked-assembled version of Thales LUNOS or ANVIS-6 (for pilots). An indigenous Thermal Monocle is beeing developed by the Army as far as I know.

[General Lee]

Originally Posted by Ulzgoroth

The Basic Set does not assume human characters have their heads clamped in place.

Would you concur with me that a person looking straith that have a FoV of 180º is better off than one with FoV 40º? One could actually see more even using NVGs, but for me that justifies the penalties for use them without the Perk Green Eyes.

[Anthony]

Originally Posted by Ulzgoroth

The Basic Set does not assume human characters have their heads clamped in place.

Sure, but it's the closest match to a 40 or 97 degree FOV.

[Tzeentch]

For NVGs like the AN/AVS-10 eliminate No Peripheral Vision (p. B151) for 2¥ normal cost. You should be able to stack this with other NVG options (that may appear in a future Pyramid article) like the newer lightweight models (AN/PVS-31) and low-profile systems (AN/PVS-21).

At least, that's my take on it that seems simplest and consistent with existing designs.

[General Lee]

Originally Posted by Tzeentch

For NVGs like the AN/AVS-10 eliminate No Peripheral Vision (p. B151) for 2¥ normal cost. You should be able to stack this with other NVG options (that may appear in a future Pyramid article) like the newer lightweight models (AN/PVS-31) and low-profile systems (AN/PVS-21).

At least, that's my take on it that seems simplest and consistent with existing designs.

Interesting. Googling about the AN/PVS-21, I found that this new type of NVG have an intensified FoV of 40º and an unaided FoV of 165º. I think that this NVG represents an article of early TL9, because it permits data fusion, functioning as a real HUD.

From these facts I have a question: It is possible to aim with binocular NVGs?