NOTES ABOUT NIGHT VISION. 

(​As I think to mention them.)


Using Generation 3 monoculars for sighting devices can be carried out a number of ways. For example using clip on devices both in front of and behind the actual sighting device. (Scope, Red Dot etc.)

These units have there own good and bad points. For example image intensifying NV will have a significant system loss when a clip on is mounted behind a normal daylight scope due to the losses in the sight lenses, whereas if it is mounted in front of the scope there is no additional loss and the NV device's own sensitivity will be retained along with the users normal shooting position will be retained.

There is a lot of discussion regarding the use of lasers for the aiming point. Yes this can be done but with Generation 3 units caution must be a priority! If the laser is too intense then damage can be done to the NV core.

While laser pointers are quite often used to indicate a target with night vision it is recommended that they are not fixed where the bright spot is always remains at the same point all the time as they would be when used as a sighting "reticle".

The intensity can be adjusted with some lasers but not all. It will also depend on how close the spot (Range) is from the NV this will alter the apparent brightness.

Colour is also a factor in their use, green for instance at about 520 nm, will not be detected as well as red, 635 nm, due to the NV item being designed to operate in the dark where the ambient light is tending more to the IR and red spectrum. Even though to the human eye it will appear brighter than the same power in red. It is also advised that IR lasers can also damage the unit as well.

Another little problem with lasers, is that if there is any humidity, dust or similar in the air you will have a very annoying beam of light visible in your NV. 


Generally lasers are more value when used in conjunction with straight optical devices for sighting. 



Quote from a night vision dealers web site

Higher    -     FREQUENCY     -      Lower

Visible light spectrum

gamma ray ~ X-ray ~ Ultra violet  

Be careful with some technical information provided !


OK You are reading "stuff" on this site too, but have a look below. This is a technical explanation written by a prominent, long established Australian night vision provider. It is WRONG ! 

As frequency  increases wave length decreases.  Visible light is of higher frequency (Shorter wave length) than Infrared light. 

                                i.e. Infrared wave length from 1000 nm down to about 700 nm. Frequency 300 Ghz to 430 THz

​                                       Visible light wave length from 700 nm to about 400 nm. Frequency 430 THz to 790 THz

​There is so much wrong information put about by persons who you would expect to be a reliable source of information, where you assume they know what they are talking about.  










As the plate heats up further, the frequency will rise and the plate starts to glow red, at a higher frequency than Infrared, (into the visible red spectrum), which we will see with our eyes.  

If you are still in doubt, go back and consult your high school physics books !                                                                                                                                                                                       

WARNING !

​There is now a Chinese company "making" thermal scopes in the UK to appear to be a British company, they cannot even spell the company name the same way twice on their web site????                                      With just a quick look at one of their comparable thermal rifle scopes, based on magnification etc. would cost you here in Australia the same price as a GSCI unit but regardless of their "specification" sheet only provides half the detection distance, requires 4 X CR123 batteries for 8 hours use as against 4 X AA batteries for 12 hours use. The lens specification / size CANNOT be correct. I ask why would anybody purchase from them?

Be careful very careful when deciding on what and where to buy. 

LEGALITY of NIGHT VISION in AUSTRALIA

Infrared

nm

This is complete and utter RUBBISH ! Thermal IS affected by these things, all thermal imaging is. It is not a fault, that is just the way it is. Detection distance is reduced and the image will look "grainy". It will still work better than image intensifying NV, but it will be reduced performance.  Imagine the feeling if you had purchased an expensive piece of gear with the above in mind. 

Is night vision legal in Australia and if so is there any restrictions?

Basically is is completely legal, No restrictions apply to owning and using night vision under Australian law, image intensifying or thermal imaging.

There are however some conditions on how it is used in some states. e.g. You may not use it for hunting. Check in your own state.  

I feel that it will / should be obvious to most people, that illegal observations and terrorist use will be a no go.

Importing of night vision has some requirements, such as you cannot import US made Gen 3 night vision or US made thermal rifle scopes without an ITAR approval. This is not impossible but is very difficult and expensive to do. Once you have any night vision equipment, regardless of any ITAR restrictions or not, you may NOT export it for any reason, even for repair, without Australian Customs and DECO (Australian Defence Department) permits. Even though some may have done so at some time and not been caught. It is a serious offence if you come unstuck !

Once you have signed for a "controlled" item, you may resell it within Australia, but for your own protection you should obtain a statement from the purchaser similar to the one you originally signed. 

Australian Shooting Services can assist with this for items purchased through them if ever needed.

The GSCI NV equipment we import is subject to an export licence from the Canadian Government and is controlled ownership within Australia but has no restrictions as to use, other than those mentioned above.

RECORDING FROM NIGHT VISION


Should you decide to take video recordings from your NV it is probably worth knowing that most video recorders available for this use are not high spec units, regardless of the stated video "size". These units generally only record every alternative line, not in pairs as professional units do. This will not cause any grief when it comes to viewing the clip, but can sometimes, not record some horizontal lines of your reticle because at times they happen to coincide with the "missing video" lines.

​CHOOSING A NIGHT VISION ITEM


It is not always a simple matter to choose. Do you want or need thermal or image intensifying? Once you have decided on that the next step is to decide what level of performance you need. Don't be fooled by "good advertising" or price only. If you need commercial or professional           equipment, cheap Gen 1 or basic thermal will NOT do the job for you. You will see these low level items advertised for commercial use, do NOT be fooled!                                 

Once you require that level of performance you must look at at no less than Gen 2+ for image intensifying with no less that 60 line pairs per mm and an FOM of no less than 1250. 

For thermal nothing LESS than Pulsar XD Series or higher specs. in either rifle scope or monocular.


Having trouble sighting in a thermal scope? It is normally quite workable to use 4 - 5 layers of standard kitchen aluminium foil, preferably with a matt black card behind which will provide the "temperature difference" required to see the aiming point, day or night. Do NOT be tempted to use a tiny area of foil with the idea that it will give a more precise aiming point. It does not really help with accuracy. A square or circular piece around 75 mm is good.            If you really can't manage with that, for whatever reason, we can supply a 12V heated target if required.

More stuff.


Using additional infrared illumination to obtain greater "range", especially with lower grades of image intensifying NV on dark nights.............

Just remember that when you use these items you are going to be showing a bright red light toward your target ! The radiated light may indeed be invisible to you, but should you look back at the source you will see a bright red light. This tends to negate your intended "stealth", the very thing you are tying to achieve by using night vision equipment. The suggestion put forward by people recommending low specification NV equipment and high powered IR lights is rather pointless if you defeat the whole purpose of being unseen. This is apart from all the other limitations of low spec items.
 As you increase the output power, the intensity of you red beacon becomes even brighter and can will be even more detrimental with wary game. NOTE, some animals (especially nocturnal ones) can actually see the infrared light
as well as "the bright red beacon" you have provided.  

Covert IR frequencies will help with the apparent "red light", but they will still see the IR any way. The natural light available at night has a high content of infrared light as well as any visible light we see.


As noted in pages above, the maximum detection ranges quoted in specification charts are for IDEAL atmospheric conditions.

​Any rain, fog, smoke and even high humidity will reduce this distance, and obviously recognition and identification ranges as well. Depending on the extent or degree of these this will be from slight up to greatly reduced. This applies to all forms of night vision, image intensifying and thermal. 

Just recently I attended a "Shot Show" here in Western Australia. While I was there I visited a certain Thermal Imaging suppliers stand and enquired about the performance of their products, where the salesman proudly stated that with one of their models he could distinguish the difference between a cow and a deer at 3 kilometers !

Now that is interesting as the best model they have is one that has a DETECTION distance of 2.5 Km. That means at 2500 m you will see just a few pixels ONLY, of the specified target size (human), OK, so a cow / deer is bigger than that, but it will be NO MORE than a "dot". You will NOT be able to tell what it is at 3000 m.

Now how would you feel if you had outlaid significant thousands of dollars based on the "sales persons" claim and when you actually used the item and found it did NOT perform to those claims? No recourse there, because that is not what the specifications say, and the sales person says "I don't know who told you that, it certainly

wasn't me". ( What then??)

So be careful, VERY careful of lies that some people tell.

Wave length