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Night vision pointers please
11 September 2018, 17:51,
Night vision pointers please
I'm finally getting round to addressing my lack of night vision technology , the need arises for dog walking purposes , my terrier "Charlie" has spent the last two winter's with various light's dangling of him so he can be spotted whilst walking after dark , he has wrecked or lost so many I think I need a diffnerent tack I also worry he will get caught up by some them and trap himself or worse! So I think it is time to try a night vision monocular , tis also a sneaky way of adding a use full piece of kit to the preps , i want fairly compact(pocket sized) run of regular batteries not the button type and preferably a brand i've heard of but not mega expensive , one last thing should I be only looking at digital or are the older gen 1 light intensifies wort considering?
Nothing is fool proof for a sufficiently talented fool!!!!
11 September 2018, 19:11,
RE: Night vision pointers please
EDC Lights and A Night Vision Primer

If you've ever had to find your way out of a large building after the power goes out you can appreciate the value of having at least a small light with you as Every Day Carry (EDC). A tiny LED on your zipper pull or keyring beats nothing. The point is to always have SOMETHING.

I have Fenix EO1 single-AAA cell LED lights on the zipper pulls of all outer garments, and carry one on my key ring all the time. These are inexpensive enough that you can buy multiples and stash them everywhere, your keyring, in personal first aid or survival kits, etc.

In my Get Home Bag I keep a Petzl Tactikka Plus Headlamp and spare batteries. I prefer LED lights because they are more rugged, and have longer run time on a set of batteries, adequate to last all night if working a 12-hour shift. In heavy use of Xenon lamps on searches you must carry both spare lamps and spare batteries. My needs these days are mostly in finding things in my pack, in the car or cockpit at night, and for walking trail illumination. You must wear protective safety glasses with side guards whenever moving around at night.

The Petzl headlamp with red filter is recommended for night flying in general aviation, when used at its lowest 5 lumen setting. Red is the only color that does not bleach out your rhodopsin and degrade night vision. Green light at very low levels has much less effect than white light. In the days before military pilots flew while wearing night vision goggles, night training involved wearing red goggles for an hour before flying, to protect from exposure to bright lights, exclusively using red lights in flight planning rooms, keeping lights off on the flight line and avoiding flying anywhere near intense light sources. Night training flights were planned for the darkest times when the moon was not full or before it rose or after it set below the horizon. If you want the best night vision avoid bright light religiously, get plenty of rest, do not smoke, stay at low altitudes and use supplemental oxygen when at cruising altitude.

Military aviators in the Vietnam era were issued a simple 2-AA cell pen light with white bulb and sliding red filter for night cockpit use. This was used mostly for writing ADC clearances on the kneeboard on night ops, but in Indian Country could be very cautiously used as an evasion light also. Back then an evasion light was no light at all, or as little light as possible exposed for no longer than absolutely necessary. Safe, stealthy movement depends on staying still until your eyes are fully dark adapted, then moving slowly, quietly and cautiously, traveling at night to avoid detection and hiding in dense vegetation during the day.

Movement attracts the eye, and so does any light. A moving light at night especially draws attention and gets investigated. Even a tiny LED is highly visible for a mile or more with the naked eye and several times that with FLIR or NVG. If a downed aircrewman in a hostile area incautiously leaves a light unprotected for more than a few seconds and moves around. it may be seen and increases risk of detection or capture. Side shields are absolutely necessary for any evasion light.

The human eye performs poorly at night. Fatigue has great influence at night. The retina is the first and fastest part of the body to react to reduction of blood oxygen. Cigarette smokers start out with an immediate night vision problem. Complete night adaptation of the eye to darkness takes over 30 minutes and be destroyed in seconds. The cones used for color vision are centered in the eye but are slow to adapt and then only by a factor of x 100. Rods make it so we can see at night but not in color and are spread to the sides in the back of the eye. They are more sensitive at night by a factor of x 100,000. Rods take 30 minutes to recover from a bright light shock.

The oval shaped region retinal blind spot cannot see light, but binocular vision compensates for this in daytime. At night we often are unable to see objects if we look directly at them. To see at night do not look directly at what you want to see because your central vision is inoperative at night. Looking off center at night uses your peripheral vision which is 100,000 times more sensitive than central vision at night. Your eyes can be adapted to night vision by wearing red glasses, patching one eye and using dimmed lighting.

No matter how well you do this one muzzle flash in your face destroys it all!

Your visual adaptability to light/darkness is reduced 50% every eleven years of your life. Experience and frequency of night flight is the best compensation for this loss. Any bright light effectively reduces night vision. You might try protecting one eye from light until airborne. Try wearing sunglasses at dusk.

Vitamin A is a vital element for night vision and adaptation. Vitamin A deficiency will make a significant difference in night vision. However excessive intake of Vitamin A will not give an apparent improvement.

Ample oxygen is necessary for adequate night vision more so than day vision. Above 4000 feet AMSL supplemental oxygen improves night vision. The most dangerous aspect of this is that the pilot has no way of knowing that he is not seeing as well.

Wearing of sunglasses during the day is one way to improve your night vision. Neutral gray glasses with UV resistant coating are best. At night, red lenses will absorb blue light and aid dark adaptation. Restrict any use of bright white light at night since even a momentary flash will destroy night vision. Use blue, green or red LEDs.

Should blur interfere with the things you see at night, it may be indicative of night myopia. Squinting will help some or the use of glasses. If the eye is unable to focus on anything at a distance at night it may be having space myopia. Keeping the eyes moving can help limit these effects that are made worse by staring.

Objects are harder to see at night just because they are less well defined around the edges. This makes things appear farther away than they actually are. The requirement for corrective lenses (if you wear them) at night is much greater than during daylight.

Hope this helps.

73 de KE4SKY
"Almost Heaven" West Virginia
12 September 2018, 15:39,
RE: Night vision pointers please
Anyone and everyone needs a night vision setup just as much as they need a torch. In a hostile situation they need the NV gear MORE than they need a torch.

What you need as your night vision device will be controlled by two variables, what do you expect and how much can you pay.

for "dog walking" you will probably be just as well off with some of the old generation 1 gear which is cheap as chips most places.

My outdoor suppliers flood me with adds for all sorts of NV gear so your choices are infinite. What will be best for you is up to you.

I have a set of binos that go out to 100m with image definition but not recognition clarity. I could tell there was a dog standing there but I could not tell if it was MY dog! They cost $50 us.

I also have infared capability to install on my scoped rifles. It is Gen 1 technology much like that used in WW2. It sends a beam out and that IR light is scanned by an IR camera and shown on a screen. It has amazing clarity and I can identify targets and shoot things as small as a rat accurately out to 100m. Cost on that was $125 us.

You can get very good monoculars for about $400 and the cost go up to "what are you willing to pay" and performance to match.

About all I can tell you about the expensive devices is what my friends that own them say. But most of those devices are intended to be mounted on rifles and not carried in the pocket during dog walks.

Have you considered attaching a chem-light to Charlie's collar. You can buy a lot of chem-lights for the cost of a NV setup. Buy them from the kids toy section and not the sporting good section, they are much cheaper bought as toys.
12 September 2018, 16:47,
RE: Night vision pointers please
I'm just dipping my toes in the water with the first one , was budgeting between £100 and £200 , want it to have a fairly long run time preferably on AA batteries compact as possible given the battery choice , and able out to at least 100m ... there are plans for a rifle mounted second unit.
Nothing is fool proof for a sufficiently talented fool!!!!
13 September 2018, 15:48,
RE: Night vision pointers please
There are so many choices out there it is difficult to advise but if you are just starting out you might consider a Fire Field system.

It meets all your specs using three AA batteries and having a run time of 12 hours with decent range and quality.

They are probably available on British Amazon so check there. I am very certain that NV technology is on the "do not smuggle into the UK" list. Not illegal, just not allowed to ship from here to there.

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