not planned Night Vision goggles with symbology display unit (SDU)

[icuham]

Presently, the AH-64 offers the IHADSS or night vision goggles but with NVGs on it's not possible to see any flight and targeting symbology while using the NVGs.  The pilot is left with only IHADSS in a single eye, or must constantly switch back and forth between NVGs and IHADSS, which isn't ideal.

In real life this has been overcome using a couple of options, at least one of these should be made available in DCS:

Option 1: Single NVG monocle for left eye in addition to IHADSS in right eye.

This solution is described in "Apaches Over Libya" by Will Laidlaw:

"Over my left eye I brought down a single Night Vision Goggle (NVG) tube attached to my helmet.  The left eye now had two jobs: look inside at the MPDs and look outside through the NVG.  The right eye continued interpreting the HMD symbology with infrared video superimposed from the FLIR mounted on the nose of the aircraft..."

This solution would be well implemented if it allows VR users to look 'underneath' the monocle as you can in the SA-342 so that your left eye can read the MFD in the lower view and see an NVG view in the predominant upper view.

Option 2: Implement a dual-eye Symbology Display Unit (SDU)

This solution is described in "USAARL Report No. 2007-05 Apache Aviator Evaluation of Dual-Technology Night Vision Systems in Operation Iraqi Freedom (OIF) Urban Combat (Master’s Thesis)" By J. Kevin Heinecke (UTSI) Clarence E. Rash (USAARL) Richard Ranaudo (UTSI) Keith L. Hiatt (OCS-FORSCOM) available here: https://www.researchgate.net/publication/290612345_Dual-sensor_use_in_the_AH-64_crew_station_for_urban_combat_in_operation_Iraqi_freedom/link/5b79d098a6fdcc5f8b55a2c5/download

"The U.S. Army has temporarily authorized the use of an improved version of NVGs modified for use with a symbology display unit (SDU). The SDU mounts to the pilot’s visor and provides the NVG wearer with full flight symbology representation identical to that provided by the IHADSS. An additional feature of the SDU design is that it allows for line-of-sight acquisition use of the aircraft’s onboard weapons system (U.S. Army Research, Development and Engineering Command, 2005). This system is only authorized for use by units operating in the combat theater and at the discretion of the individual commands."

More info is required but this solution seems to offer a dual eye NVG system with the full IHADSS symbology overlaid on the right eye view which may minimize eye strain for VR users in DCS night missions.  The same solution of offering a small space to look 'underneath' the goggles to see MFDs may work well here too.  Perhaps these could be selected as cockpit options in the specials menu at some point.

USAARLTR2008-05.pdf

[Talonfox]

Another technique that I teach to new pilots is to have a video page up on one of the MPDs. A video page mirrors both the symbology and the FLIR picture that would normally be displayed on the HDU combiner lens. NVGs down, the pilot still has the same basic cross-check (ie. center symbology, altitude, heading, picture, center symbology . . . ) and just glances down from time to time for the pertinent flight information. It just takes time and iterations to become proficient.

Good Hunting

[icuham]

@TalonfoxThis sounds like a decent real life solution where you could see past the NVG edge by looking down, and didn't yet have an SDU available.  It seems like IRL the FOV vertically of something like ANVIS should be about 40 degrees.  In DCS VR the entire field of view is pretty much full of NVG (ie. >90 degrees in an HP Reverb G2) so with this filled we still have to raise the goggles in DCS to see the MPD video page right?  Since you wouldn't have to lift the NVG in real life, the present NVGs in DCS aren't even a sufficient solution without the ability to see past them, imo.  If we could see past them (as you can in the Gazelle) then this suggestion is a somewhat more workable solution, but even the US Army seems to have concluded that it could have been better... 

A note from the report attached above - there was a split opinion in RL pilots about ease of use looking under the NVGs and an overwhelming preference for NVGs with symbology (94.7%):

"To further understand the use of MPD displayed flight symbology, pilots were asked to state the ease with which they could view the data while using ANVIS. Recall that pilots wearing the ANVIS system must look below/under the HMD to view the aircraft’s MPD. The responses were nearly evenly split between “Fairly easy,” 12 (31.6%), and “Fairly difficult,” 10 (26.3%). Of the remaining responses, 5 (13.2%) respondents report viewing is “Very easy,” 5 (13.2%) reported a “Neutral” response, 3 (7.9%) reported viewing is “Very difficult,” and 3 (7.9%) reported they did not use symbology, up from two reported on the previous survey question. figure 32 shows the complete results for this survey question."

"The U.S. Army countered these problems by allowing the use of NVGs in the AH-64 cockpit while scheduling a modernization of the IHADSS’ infrared imaging system, in essence allowing the AH-64 pilot the “best of both worlds,” image intensification and infrared."  <- Just like the 94.7% of pilots above I think most DCS players would like this solution too, especially given that the system was deployed. Might even help us avoid headaches from bright lights in one eye and darkness in the other in game too.

[Talonfox]

Icuham, point well made. If looking under the goggles is not an option in DCS then perhaps the SDU would be a viable option.

Interesting background information and good on you for finding actual references. In reality, image intensification technology (I2) is being blended with FLIR to provide the best of all worlds, and in the future pilots may well be using a full-face visor with video presented on the visor itself. All exciting stuff.

Once again, good work digging up the reference!

Good Hunting!

[kgillers3]

3rd option. Limit NVG FOV. So you can just look under it   

[Talonfox]

I would be onboard for that!

[da_drake]

If we had vertical FOV limiting in VR as well as the "left, right, both eye" options for the NVG, like we have for the Apache's HDU and the HMDs in some jets, it would be incredible. Even the latter would solve problems in a lot of modules. Not that that's entirely realistic, but neither are the global, somewhat modern "looking" NVGs that you can use in warbirds.

Edited March 21, 2022 by da_drake

[seven10]

All these options sound like they'd be an improvement over the current option. The current nvg mask looks like a monocle vs the binocular options both the pilot and cpg are wearing. It would be excellent if one could be flipped or they could be looked under as easily as it is in reality.

[FC_Schaefer]

Nice presentation. I'm also of the opinion of limiting the NVG FOV. Which option does Eagle Dynamics feel is easiest to implement? Which is "safest"?

[bradmick]

I’ve never seen an SDU in my time in Apaches. Using the SDU requires removal of the HDU from the cockpit. The primary means of flying the aircraft is with the FLIR and goggles are an augment to the gunner in the front seat. You learn where your “index point” is for target handovers over time when using the goggles. Overall this would be an unrealistic addition (the sdu) for the aircraft because it’s just not used. 

[Scaley]

This topic comes around in other aircraft as well, and it seems is basically caused by the odd fact that the NVGs in VR fill the entire field of view. I have no idea why ED chose to do this, but if they fixed that it would solve similar problems across a lot of airframes, rather than specific fixed per aircraft (like SDU for the Apache)

[icuham]

On 4/1/2022 at 7:27 AM, bradmick said:

I’ve never seen an SDU in my time in Apaches. Using the SDU requires removal of the HDU from the cockpit. The primary means of flying the aircraft is with the FLIR and goggles are an augment to the gunner in the front seat. You learn where your “index point” is for target handovers over time when using the goggles. Overall this would be an unrealistic addition (the sdu) for the aircraft because it’s just not used. 

This approach seems completely different from Laidlaw's description of how they flew in Libya, but it certainly makes sense that different approaches would be used by different operators in different contexts.  Night lighting in DCS isn't quite realistic yet, and I'm not sure using FLIR only would be a comfortable or enjoyable experience in VR for extended periods.  Many of our friends will simply opt out of that rather than deal with the discomfort in game.  ...If so many real Apache pilots also showed preference for NVGs with symbology, why would players prefer an experience without it?  I'd rather have a workable solution that players enjoy in the game even if not all Apache pilots employed it. If that's not SDU, then either Laidlaw's solution of a single monocle or fixing the NVG FOV in VR seem like options that would make the experience more enjoyable for a player. 

[Raptor9]

1 minute ago, icuham said:

If so many real Apache pilots also showed preference for NVGs with symbology, why would players prefer an experience without it?

Given a choice strictly between NVG's with symbology versus NVG's without symbology, I would agree that the majority of AH-64 pilots would prefer it with the symbology.  However, that is a raw comparison that doesn't take into account other factors, such as the fact that if you use the SDU, you lose the option to use the HDU and associated FLIR. At least in the US Army the vast majority of AH-64 pilots preferred to use the PNVS FLIR and not the NVG's, even with the SDU fitted.  As Brad mentioned, the SDU was hardly ever used in real-life because of this, despite the equipment being available. So it is either one or the other (NVG's with SDU or HDU/PNVS), whereas with non-SDU NVG configurations you have the option of using either NVG's or HDU at any time, depending on your preference or tactical situation.

NVG's and FLIR have their pros and cons, but the preference was solidly in favor of the HDU/PNVS over NVG's with SDU.  The SDU was divested from the fleet because they were hardly used.

On the DCS side of things, I do agree that in VR the NVG FOV should be reduced to simulate how the NVG's would be worn and used in real-life.

[Crptalk]

I think NVG with SDU would be a nice addition if anything because turning on FLIR almost halves my FPS in VR.

[jnr4817]

I modified the nvg mask size to be more realistic. Now you can actually Look under your goggles and scan.

Anyone can do it. It’s very easy and you can make it OvGme compatible. 

Edited April 18, 2022 by jnr4817

[icuham]

On 4/17/2022 at 7:53 PM, jnr4817 said:

I modified the nvg mask size to be more realistic. Now you can actually Look under your goggles and scan.

Anyone can do it. It’s very easy and you can make it OvGme compatible. 

 

Can you share exactly what you did to change this please?  I think a lot of us would like this change.

[jnr4817]

Here is the file I modified for use with OvGme. When I get home I’ll make a full post. It changes the mask size number in the nvd_common.hlsl lua.

#ifndef _NVD_COMMON_
#define _NVD_COMMON_

#include "common/context.hlsl"

#define MASK_SIZE (1.0/0.45)

float getMask(float2 c, float mul) {
	return saturate(mul*(1 - sqrt(dot(c, c))));
}

float2 calcMaskCoord(float2 projPos) {
	return float2((projPos.x - gNVDpos.x) * gNVDaspect, projPos.y - gNVDpos.y) * MASK_SIZE;
}

float getNVDMask(float2 projPos) {
	float2 uvm = calcMaskCoord(projPos);
	return getMask(uvm, 10);
}

#endif

I use 0.45

located at dcs install folder  Bazar/shaders/posteffects/Nvd_common.hlsl

NVG_Size.zip

Edited April 20, 2022 by jnr4817

[kgillers3]

On 4/20/2022 at 12:06 AM, jnr4817 said:

Here is the file I modified for use with OvGme. When I get home I’ll make a full post. It changes the mask size number in the nvd_common.hlsl lua.

#ifndef _NVD_COMMON_
#define _NVD_COMMON_

#include "common/context.hlsl"

#define MASK_SIZE (1.0/0.45)

float getMask(float2 c, float mul) {
	return saturate(mul*(1 - sqrt(dot(c, c))));
}

float2 calcMaskCoord(float2 projPos) {
	return float2((projPos.x - gNVDpos.x) * gNVDaspect, projPos.y - gNVDpos.y) * MASK_SIZE;
}

float getNVDMask(float2 projPos) {
	float2 uvm = calcMaskCoord(projPos);
	return getMask(uvm, 10);
}

#endif

I use 0.45

located at dcs install folder  Bazar/shaders/posteffects/Nvd_common.hlsl

NVG_Size.zip 1.08 kB · 1 download

 

I'll give this a go as well, maybe I'll use NVG's more, thanks! 

[jnr4817]

4 hours ago, kgillers3 said:

I'll give this a go as well, maybe I'll use NVG's more, thanks! 

Try it man. Made NVG's very realistic in VR.

[Scaley]

Also 
https://www.digitalcombatsimulator.com/en/files/3316348/

 

[lefuneste01]

Or :

 

[icuham]

Before I go trying each of these.... Do they all pass IC?

[Dangerzone]

On 5/2/2022 at 7:25 AM, icuham said:

Before I go trying each of these.... Do they all pass IC?

Did you ever get you answer for this icuham? I'm curious to know as well.