Night vision with NVG since version 2.7 - How to measure clarity?

[PB0_CEF]

Since DCS version 2.7 I have noticed that night vision goggles on particularly dark nights (without or with very little moon) were ineffective to fly in in the middle of the
terrain. 
My main question is not to know if it's realistic or not (even if that interests me anyway: hum  but rather to know how we can know in advance the degree of brightness of a
 DCS mission ?
Indeed during night missions it is no longer possible for me to attempt low altitude infiltrations in the relief when the night is very dark and I have not found a way to know this in 
advance in the briefing.
Of course I am not talking about missions that I would have edited myself since in this case the last tool made available by ED gives some information on the moon at a 
given date and time (and even that does not give a value of clarity) but rather missions created by other people or better by automated generators like DCE for example: hum:
Ideally, the goal will be to have a clarity value or an equivalent allowing the definition of NVG use thresholds according to the type of missions. It would then be possible to 
generate only compatible missions or to change the weaponry to adapt to night visibility conditions.
Besides, if these conditions are realistic, is there this type of information in a real brief for night missions? low altitude 

Edited November 17, 2021 by PB0_CEF