[Ghost Rigger]

So I'm building a stealth poncho so that I can be much sneakier at night. Not wanting to break the bank on ruthenium polymer coating, especially when ultrasound and motion detectors ignore it anyways, I've opted to go for voidblack coating and thermal damping 6. Thing is, I'm not quite sure how the voidblack coating interacts with non-standard vision types. Obviously, anything not based on light (ultrasound, thermal) will ignore the penalty, but what about low-light vision? Cutting Aces says that voidblack coating applies " in dark or heavily shadowed areas"; does having low-light vision change what counts as "dark or heavily shadowed"?

Somewhat related, does a full-body armor suit with voidblack coating or ruthenium polymer coating require that the modification be on both the main body of armor AND the helmet? Asking for the group's physical infiltrator.

[firebug]

I think it would.  My understanding of that would be that the armor adds to the penalty from Dim Light and Total Darkness.  Partial Light and Full Light do not get the beenfit from the mod.  Since Low-Light Vision says "Treat Partial Light and Dim Light as Full Light", it wouldn't affect someone with that trait.

Also, in my games at least, those kinds of mods are applied to the armor and I just have them affect the helmet too, though I don't allow normal armor mods (like Nonconductivity or Thermal Dampening) on helmets or other armor accessories.  That way there's no confusion on what stacks and it stops dumb things like having shock weave on your helmet, or having to pay the exact same amount to get ruthenium on "everywhere but my head" as "only my head".  It's probably not how it's intended to work, but it needs errata.  Some GMs might say it's not possible, for instance, to have body armor that counts as "almost full" and then to combine it with a helmet with the coating.

[Ghost Rigger]

Hm, that makes voidblack coating a lot less useful given how easy it is to obtain low-light vision. Oh well, another one for the "useful against people who really weren't equipped to deal with shadowrunners anyways" list.