Thread by @SwiftyTac

I'm bored so here's a thread on better getting into the NVGs game. I'm not ultra tech savvy and I don't really like jargon, but you can't really gloss over it if you're trying to acquire NVGs without it being hand selected for you by a professional. #nvgs #nightvison #nods

So, if you style yourself as just wanting answers to the test, maybe this will help out. @VeritasVital @ouroboros_outis both want nods so this is for them. For training, see @opfor8r.

Specifications are the most important aspect of NVGs because they ultimately dictate the price, so you better know what kind of horsepower they have. Knowing performance helps you split hairs, determine needs, and figure out a budget you can afford. /spec1

Also for clarification, tubes refers to the actual image intensifier (I²), the engine so to speak. Housings is what the tubes go into. NVG/nods are the complete package.

𝗦𝗡𝗥/𝗦𝗶𝗴𝗻𝗮𝗹-𝘁𝗼-𝗡𝗼𝗶𝘀𝗲 𝗥𝗮𝘁𝗶𝗼 – how well a tube transmits light against visual noise into an image. Low SNR results in a very noisy image, getting worse with less light, higher SNR yields a better image in those conditions. +30 is superb, below 20 is bad. /spec2

SNR is arguably the most important spec of nod. Varying specs can look the same in a controlled environment, but SNR determines how well you can resolve what you're looking at as ambient light is taken away. /spec3

𝗥𝗘𝗦/𝗖𝗲𝗻𝘁𝗲𝗿 𝗥𝗲𝘀𝗼𝗹𝘂𝘁𝗶𝗼𝗻 – actual image quality a tube can produre at it's center. Higher is better but is not too important unless magnification is a concern. 57 is baseline, above 81 is superb. /spec4

𝗘𝗕𝗜/𝗘𝗾𝘂𝗶𝘃𝗮𝗹𝗲𝗻𝘁 𝗕𝗮𝗰𝗸𝗴𝗿𝗼𝘂𝗻𝗱 𝗜𝗹𝗹𝘂𝗺𝗶𝗻𝗮𝘁𝗶𝗼𝗻 – the lowest levels of light a tube can detect, the lower the EBI the better. Can be tricky because the difference can be negligible until temperature is taken into account. Higher temperature... /spec5

...negatively affects EBI, but even then that's at significantly low light levels IE inside a building. EBI is important but not the most absolutely critical metric like some people say. Below 1.0 is superb, above 3.0 is bad. Images are from Nocturnality on IG. Spec/6

𝗙𝗢𝗠/𝗙𝗶𝗴𝘂𝗿𝗲 𝗼𝗳 𝗠𝗲𝗿𝗶𝘁 - a very basic specification that gives you a rough idea of the quality of a tube, probably the most commonly way to advertise it. FOM = SNR • RES. So an FOM of 2112.8 is from 27.8 SNR & 76 RES. Very high FOM is good, but not... /spec7

...a guarantee, so get the specs first. So with a 1600 vs 1900 tubes seems obvious, but it turns out the higher tube only has 19.8 SNR to the lower FOM tube's 25 SNR, technically giving it a worse lower light image. Above 30 is amazing, below 20 SNR is bad. /spec8

𝗛𝗮𝗹𝗼 - the effect on a tube when it looks at light sources, meaning a band of light might potentially obscure what you’re looking at. The lower the halo, the better. Below 1.0 is what you want, avoid 2.0. /spec9

𝗦𝗽𝗼𝘁 - small little black spots. Typically defects from manufacturing or outright damage from light sources. They can be very negligible dots or very distracting blotches. The worse the spot or blem, the lower the price of the tube. /spec10

There are other specs such as photocade sensitivity and gain, but typically knowing the previously mentioned specs typically entails a good tube. While I did say specs are important to know, it's just as important to not get caught up in chasing better numbers. /spec11

Most people will not tell the immediate difference between 2200 FOM tubes from 2400 FOM, not without significant time spending with both in a controlled environment. So you can easily shave a grand or more going with slightly lower specs. /spec12

Very important to note, mil-spec/surplus tubes are largely 𝗯𝗲𝘁𝘁𝗲𝗿 than consumer grade tubes. The govt gets higher grade tubes via contracts & anything that fails QC for it maybe resold by dealers to you. Said mil-spec tubes have specific identifiers... /spec13

...such as Elbit mil contract tubes will be labeled as MH22. Further convoluting it is the Army NVG acquisition system known as Omnibus or OMNI, with each contract (1 to 8) having specific minimum specs. It's a headache to understand even for me so just talk to sellers. /Spec14

If you want to know more and have more direct & concise answers to your question, NocturnalityGear & Gooning Gear LLC are probably the most active dealers you can refer to for information. I personally went through Nocturnality for my dual tubes.

I'll continuously add to this but for now, I tried to keep it stupid simple.